Broadcast signal transmitting apparatus, broadcast signal receiving apparatus, broadcast signal transmitting method, and broadcast signal receiving method

ABSTRACT

Disclosed herein is a method of receiving a broadcast signal. The method comprises receiving the broadcast signal; an Orthogonal Frequency Division Multiplexing (OFDM) demodulating on the received broadcast signal; parsing at least one signal frame from the demodulated broadcast signal to extract service data or service component data; converting the service data or service component data into bits; decoding the converted bits; and outputting a data stream comprising the decoded bits.

This application is a claims priority to Provisional Application No.62/099,594 filed on 5 Jan. 2015 in US the entire contents of which ishereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a broadcast signal transmittingapparatus, a broadcast signal receiving apparatus, and broadcast signaltransmitting and receiving methods.

Discussion of the Related Art

As transmission of an analog broadcast signal ends, various techniquesfor transmitting and receiving a digital broadcast signal have beendeveloped. The digital broadcast signal can include more video/audiodata than the analog broadcast signal and further include various kindsof additional data as well as the video/audio data.

SUMMARY OF THE INVENTION

That is, a digital broadcasting system may provide High Definition (HD)images, multi-channel audios, and various additional services.

For digital broadcasting, however, data transfer efficiency for thetransmission of a large amount of data, the robustness oftransmission/reception networks, and network flexibility in which amobile reception apparatus has been taken into consideration need to beimproved.

Accordingly, an object of the present invention is to provide a methodfor maximizing a frequency diversity effect using a differentinterleaving seed for each OFDM symbol pair in a Frequency Interleaver(FI).

Furthermore, an object of the present invention is to provideinformation indicating whether a frequency interleaver is used in abroadcasting signal transmission apparatus including the frequencyinterleaver.

Technical objects to be achieved in this specification are not limitedto the aforementioned objects, and those skilled in the art to which thepresent invention pertains may evidently understand other technicalobjects from the following description.

In this specification, there is provided a method of receiving abroadcast signal. The method comprises receiving the broadcast signal;an Orthogonal Frequency Division Multiplexing (OFDM) demodulating on thereceived broadcast signal; parsing at least one signal frame from thedemodulated broadcast signal to extract service data or servicecomponent data; converting the service data or service component datainto bits; decoding the converted bits; and outputting a data streamcomprising the decoded bits, wherein the signal frame comprises acontrol information indicating whether a frequency interleaver (FI) isused or not.

Furthermore, in this specification, the signal frame further comprises apreamble carrying a physical layer signaling data, and wherein thecontrol information is included in the preamble.

Furthermore, in this specification, the parsing the at least one signalframe comprises a frequency deinterleaving on the demodulatedbroadcasting signal, and wherein the frequency deinterleaving isperformed using different interleaving seeds and a single memory.

Furthermore, in this specification, the control information is frequencyinterleaver mode (FI_MODE) information.

Furthermore, in this specification, there is provided a receptionapparatus for receiving a broadcast signal, comprising a receiver forreceiving the broadcast signal; a demodulator for demodulating thereceived broadcast signal by an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme; a frame parser for parsing at least onesignal frame of the demodulated broadcast signal to extract service dataor service component data; a converter for converting the service dataor service component data into bits; a decoder for decoding theconverted bits; and an output processor for outputting a data streamcomprising the decoded bits, wherein the signal frame comprises acontrol information indicating whether a frequency interleaver (FI) isused or not.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings included to more appreciate the presentinvention and included in the present application, and constituting apart thereof illustrate embodiments of the present invention togetherwith a detailed description for describing a principle the presentinvention.

FIG. 1 illustrates a structure of a broadcast signal transmittingapparatus for a next-generation broadcasting service according to anexemplary embodiment of the present invention.

FIG. 2 illustrates an input formatting block according to an exemplaryembodiment of the present invention.

FIG. 3 illustrates an input formatting block according to anotherexemplary embodiment of the present invention.

FIG. 4 illustrates an input formatting block according to yet anotherexemplary embodiment of the present invention.

FIG. 5 illustrates a bit interleaved coding & modulation (BICM) blockaccording to an exemplary embodiment of the present invention.

FIG. 6 illustrates a BICM block according to another exemplaryembodiment of the present invention.

FIG. 7 illustrates a frame building block according to an exemplaryembodiment of the present invention.

FIG. 8 illustrates an orthogonal frequency division multiplexing (OFDM)generation block according to an exemplary embodiment of the presentinvention.

FIG. 9 illustrates a structure of a broadcast signal receiving apparatusfor a next-generation broadcasting service according to an exemplaryembodiment of the present invention.

FIG. 10 illustrates a frame structure according to an exemplaryembodiment of the present invention.

FIG. 11 illustrates a signaling layer structure of a frame structureaccording to an exemplary embodiment of the present invention.

FIG. 12 illustrates preamble signaling data according to an exemplaryembodiment of the present invention.

FIG. 13 illustrates PLS1 data according to an exemplary embodiment ofthe present invention.

FIG. 14 illustrates PLS2 data according to an exemplary embodiment ofthe present invention.

FIG. 15 illustrates PLS2 data according to another exemplary embodimentof the present invention.

FIG. 16 illustrates a logical structure of a frame according to anexemplary embodiment of the present invention.

FIG. 17 illustrates physical layer signaling (PLS) mapping according toan exemplary embodiment of the present invention.

FIG. 18 illustrates emergency alert channel (EAC) mapping according toan exemplary embodiment of the present invention.

FIG. 19 illustrates fast information channel (FIC) mapping according toan exemplary embodiment of the present invention.

FIG. 20 illustrates a type of data pipe (DP) according to an exemplaryembodiment of the present invention.

FIG. 21 illustrates a type of data pipe (DP) mapping according to anexemplary embodiment of the present invention.

FIG. 22 illustrates forward error correction (FEC) structure accordingto an exemplary embodiment of the present invention.

FIG. 23 illustrates bit interleaving according to an exemplaryembodiment of the present invention.

FIG. 24 illustrates cell-word demultiplexing according an exemplaryembodiment of the present invention.

FIG. 25 illustrates time interleaving according to an exemplaryembodiment of the present invention.

FIG. 26 illustrates a basic operation of a twisted row-column blockinterleaver according to an exemplary embodiment of the presentinvention.

FIG. 27 illustrates an operation of a twisted row-column blockinterleaver according to another exemplary embodiment of the presentinvention.

FIG. 28 illustrates a diagonal reading pattern of the twisted row-columnblock interleaver according to the exemplary embodiment of the presentinvention.

FIG. 29 illustrates XFECBLOCK interleaved from each interleaving arrayaccording to an exemplary embodiment of the present invention.

FIG. 30 is a diagram illustrating one example of a synchronization anddemodulation module of FIG. 9.

FIG. 31 is a diagram illustrating one example of a frame parsing moduleof FIG. 9.

FIG. 32 is a diagram illustrating one example of a demapping anddecoding module of FIG. 9.

FIG. 33 is a diagram illustrating one example of one example of anoutput processor of FIG. 9.

FIG. 34 is a diagram illustrating another example of the outputprocessor of FIG. 9.

FIG. 35 illustrates a coding and modulation module according to anotherexemplary embodiment of the present invention.

FIG. 36 is a diagram illustrating a demapping and decoding moduleaccording to another exemplary embodiment of the present invention.

FIG. 37 is a diagram illustrating another structure of the broadcastingsignal transmission apparatus for a next-generation broadcasting servicein accordance with an embodiment of the present invention.

FIG. 38 is a diagram illustrating a simplified TDM broadcastingtransmission system and LDM broadcasting transmission system inaccordance with an embodiment of the present invention.

FIG. 39 illustrates a framing & interleaving block in accordance with anembodiment of the present invention.

FIG. 40 is a diagram illustrating an example of an ATSC 3.0 framestructure to which an embodiment of the present invention may beapplied.

FIG. 41 is a diagram illustrating another example of the frame buildingblock of FIG. 7.

FIG. 42 is a diagram illustrating an example of a preamble format towhich an embodiment of the present invention may be applied.

FIG. 43 is a diagram illustrating another internal block diagram of theframe parsing block of FIG. 31.

FIG. 44 is a diagram illustrating the operation of a frequencyinterleaver in accordance with an embodiment of the present invention.

FIG. 45 illustrates the basic switch model of MUX and DEMUX methods inaccordance with an embodiment of the present invention.

FIG. 46 illustrates the operation of a memory bank in accordance with anembodiment of the present invention.

FIG. 47 is a diagram illustrating a frequency interleaving process inaccordance with an embodiment of the present invention.

FIG. 48 illustrates a conceptual diagram of frequency interleavingapplied to a single super frame in accordance with an embodiment of thepresent invention.

FIG. 49 is a diagram illustrating the logical operation mechanism offrequency interleaving applied to a single super frame proposed in thisspecification.

FIG. 50 illustrates the equation of the logical operation mechanism offrequency interleaving applied to a single super frame in accordancewith an embodiment of the present invention.

FIG. 51 is a diagram illustrating the logical operation mechanism offrequency interleaving applied to a single signal frame in accordancewith an embodiment of the present invention.

FIG. 52 illustrates the equation of the logical operation mechanism offrequency interleaving applied to a single super frame in accordancewith an embodiment of the present invention.

FIG. 53 is a diagram illustrating the single memory deinterleaving ofinput-sequential OFDM symbols which is proposed in this specification.

FIG. 54 is a flowchart illustrating an example of a method oftransmitting a broadcasting signal which is proposed in thisspecification.

FIG. 55 is a flowchart illustrating an example of a method of receivinga broadcasting signal which is proposed in this specification.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. The detailed description, which will be given below withreference to the accompanying drawings, is intended to explain exemplaryembodiments of the present invention, rather than to show the onlyembodiments that can be implemented according to the present invention.The following detailed description includes specific details in order toprovide a thorough understanding of the present invention. However, itwill be apparent to those skilled in the art that the present inventionmay be practiced without such specific details.

Although most terms used in the present invention have been selectedfrom general ones widely used in the art, some terms have beenarbitrarily selected by the applicant and their meanings are explainedin detail in the following description as needed. Thus, the presentinvention should be understood based upon the intended meanings of theterms rather than their simple names or meanings.

The present invention provides apparatuses and methods for transmittingand receiving broadcast signals for future broadcast services. Futurebroadcast services according to an embodiment of the present inventioninclude a terrestrial broadcast service, a mobile broadcast service, aUHDTV service, etc. The present invention may process broadcast signalsfor the future broadcast services through non-MIMO (Multiple InputMultiple Output) or MIMO according to one embodiment. A non-MIMO schemeaccording to an embodiment of the present invention may include a MISO(Multiple Input Single Output) scheme, a SISO (Single Input SingleOutput) scheme, etc.

While MISO or MIMO uses two antennas in the following for convenience ofdescription, the present invention is applicable to systems using two ormore antennas.

The present invention may defines three physical layer (PL)profiles—base, handheld and advanced profiles-each optimized to minimizereceiver complexity while attaining the performance required for aparticular use case. The physical layer (PHY) profiles are subsets ofall configurations that a corresponding receiver should implement.

The three PHY profiles share most of the functional blocks but differslightly in specific blocks and/or parameters. Additional PHY profilescan be defined in the future. For the system evolution, future profilescan also be multiplexed with the existing profiles in a single RFchannel through a future extension frame (FEF). The details of each PHYprofile are described below.

1. Base Profile

The base profile represents a main use case for fixed receiving devicesthat are usually connected to a roof-top antenna. The base profile alsoincludes portable devices that could be transported to a place butbelong to a relatively stationary reception category. Use of the baseprofile could be extended to handheld devices or even vehicular by someimproved implementations, but those use cases are not expected for thebase profile receiver operation.

Target SNR range of reception is from approximately 10 to 20 dB, whichincludes the 15 dB SNR reception capability of the existing broadcastsystem (e.g. ATSC A/53). The receiver complexity and power consumptionis not as critical as in the battery-operated handheld devices, whichwill use the handheld profile. Key system parameters for the baseprofile are listed in below table 1.

TABLE 1 LDPC codeword length 16K, 64K bits Constellation size 4~10 bpcu(bits per channel use) Time de-interleaving memory ≦2¹⁹ data cells sizePilot patterns Pilot pattern for fixed reception FFT size 16K, 32Kpoints

2. Handheld Profile

The handheld profile is designed for use in handheld and vehiculardevices that operate with battery power. The devices can be moving withpedestrian or vehicle speed. The power consumption as well as thereceiver complexity is very important for the implementation of thedevices of the handheld profile. The target SNR range of the handheldprofile is approximately 0 to 10 dB, but can be configured to reachbelow 0 dB when intended for deeper indoor reception.

In addition to low SNR capability, resilience to the Doppler Effectcaused by receiver mobility is the most important performance attributeof the handheld profile. Key system parameters for the handheld profileare listed in the below table 2.

TABLE 2 LDPC codeword length 16 Kbits Constellation size 2~8 bpcu Timede-interleaving memory ≦2¹⁸ data cells size Pilot patterns Pilotpatterns for mobile and indoor reception FFT size 8K, 16K points

3. Advanced Profile

The advanced profile provides highest channel capacity at the cost ofmore implementation complexity. This profile requires using MIMOtransmission and reception, and UHDTV service is a target use case forwhich this profile is specifically designed. The increased capacity canalso be used to allow an increased number of services in a givenbandwidth, e.g., multiple SDTV or HDTV services.

The target SNR range of the advanced profile is approximately 20 to 30dB. MIMO transmission may initially use existing elliptically-polarizedtransmission equipment, with extension to full-power cross-polarizedtransmission in the future. Key system parameters for the advancedprofile are listed in below table 3.

TABLE 3 LDPC codeword length 16K, 64 Kbits Constellation size 8~12 bpcuTime de-interleaving memory ≦2¹⁹ data cells size Pilot patterns Pilotpattern for fixed reception FFT size 16K, 32K points

In this case, the base profile can be used as a profile for both theterrestrial broadcast service and the mobile broadcast service. That is,the base profile can be used to define a concept of a profile whichincludes the mobile profile. Also, the advanced profile can be dividedadvanced profile for a base profile with MIMO and advanced profile for ahandheld profile with MIMO. Moreover, the three profiles can be changedaccording to intention of the designer.

The following terms and definitions may apply to the present invention.The following terms and definitions can be changed according to design.

auxiliary stream: sequence of cells carrying data of as yet undefinedmodulation and coding, which may be used for future extensions or asrequired by broadcasters or network operators

base data pipe: data pipe that carries service signaling data

baseband frame (or BBFRAME): set of Kbch bits which form the input toone FEC encoding process (BCH and LDPC encoding)

cell: modulation value that is carried by one carrier of the OFDMtransmission

coded block: LDPC-encoded block of PLS1 data or one of the LDPC-encodedblocks of PLS2 data

data pipe: logical channel in the physical layer that carries servicedata or related metadata, which may carry one or multiple service(s) orservice component(s).

data pipe unit: a basic unit for allocating data cells to a DP in aframe.

data symbol: OFDM symbol in a frame which is not a preamble symbol (theframe signaling symbol and frame edge symbol is included in the datasymbol)

DP_ID: this 8-bit field identifies uniquely a DP within the systemidentified by the SYSTEM_ID

dummy cell: cell carrying a pseudo-random value used to fill theremaining capacity not used for PLS signaling, DPs or auxiliary streams

emergency alert channel: part of a frame that carries EAS informationdata

frame: physical layer time slot that starts with a preamble and endswith a frame edge symbol

frame repetition unit: a set of frames belonging to same or differentphysical layer profile including a FEF, which is repeated eight times ina super-frame

fast information channel: a logical channel in a frame that carries themapping information between a service and the corresponding base DP

FECBLOCK: set of LDPC-encoded bits of a DP data

FFT size: nominal FFT size used for a particular mode, equal to theactive symbol period Ts expressed in cycles of the elementary period T

frame signaling symbol: OFDM symbol with higher pilot density used atthe start of a frame in certain combinations of FFT size, guard intervaland scattered pilot pattern, which carries a part of the PLS data

frame edge symbol: OFDM symbol with higher pilot density used at the endof a frame in certain combinations of FFT size, guard interval andscattered pilot pattern

frame-group: the set of all the frames having the same PHY profile typein a super-frame.

future extension frame: physical layer time slot within the super-framethat could be used for future extension, which starts with a preamble

Futurecast UTB system: proposed physical layer broadcasting system, ofwhich the input is one or more MPEG2-TS or IP or general stream(s) andof which the output is an RF signal

input stream: A stream of data for an ensemble of services delivered tothe end users by the system.

normal data symbol: data symbol excluding the frame signaling symbol andthe frame edge symbol

PHY profile: subset of all configurations that a corresponding receivershould implement

PLS: physical layer signaling data consisting of PLS1 and PLS2

PLS1: a first set of PLS data carried in the FSS symbols having a fixedsize, coding and modulation, which carries basic information about thesystem as well as the parameters needed to decode the PLS2

NOTE: PLS1 data remains constant for the duration of a frame-group.

PLS2: a second set of PLS data transmitted in the FSS symbol, whichcarries more detailed PLS data about the system and the DPs

PLS2 dynamic data: PLS2 data that may dynamically change frame-by-frame

PLS2 static data: PLS2 data that remains static for the duration of aframe-group

preamble signaling data: signaling data carried by the preamble symboland used to identify the basic mode of the system

preamble symbol: fixed-length pilot symbol that carries basic PLS dataand is located in the beginning of a frame

NOTE: The preamble symbol is mainly used for fast initial band scan todetect the system signal, its timing, frequency offset, and FFT-size.

reserved for future use: not defined by the present document but may bedefined in future

super-frame: set of eight frame repetition units

time interleaving block (TI block): set of cells within which timeinterleaving is carried out, corresponding to one use of the timeinterleaver memory

TI group: unit over which dynamic capacity allocation for a particularDP is carried out, made up of an integer, dynamically varying number ofXFECBLOCKs

NOTE: The TI group may be mapped directly to one frame or may be mappedto multiple frames. It may contain one or more TI blocks.

Type 1 DP: DP of a frame where all DPs are mapped into the frame in TDMfashion

Type 2 DP: DP of a frame where all DPs are mapped into the frame in FDMfashion

XFECBLOCK: set of Ncells cells carrying all the bits of one LDPCFECBLOCK

Block interleaver: An interleaver where the input data is written alongthe rows of a memory configured as a matrix, and read out along thecolumns.

Cell interleaver: An interleaver operating at the cell level.

Interleaver: A device used in conjunction with error correcting codes tocounteract the effect of burst errors.

Physical Layer Pipe (PLP): A structure specified to an allocatedcapacity and robustness that can be adjusted to broadcaster needs.

The PLP is represented to a data pipe or data transmission channel.

FIG. 1 illustrates a structure of an apparatus for transmittingbroadcast signals for future broadcast services according to anembodiment of the present invention.

The apparatus for transmitting broadcast signals for future broadcastservices according to an embodiment of the present invention can includean input formatting block 1000, a BICM (Bit interleaved coding &modulation) block 1010, a frame structure block 1020, an OFDM(Orthogonal Frequency Division Multiplexing) generation block 1030 and asignaling generation block 1040.

A description will be given of the operation of each module of theapparatus for transmitting broadcast signals.

The input formatting block 1000 can be represented to an inputformatter.

The BICM (Bit interleaved coding & modulation) block 1010 can berepresented to an encoder.

The frame structure block 1020 can be represented to a frame builder ora frame building block or a framing & interleaving block.

The OFDM (Orthogonal Frequency Division Multiplexing) generation block1030 can be represented to a modulator.

IP stream/packets and MPEG2-TS are the main input formats, other streamtypes are handled as General Streams. In addition to these data inputs,Management Information is input to control the scheduling and allocationof the corresponding bandwidth for each input stream. One or multiple TSstream(s), IP stream(s) and/or General Stream(s) inputs aresimultaneously allowed.

The input formatting block 1000 can demultiplex each input stream intoone or multiple data pipe(s), to each of which an independent coding andmodulation is applied. The data pipe (DP) is the basic unit forrobustness control, thereby affecting quality-of-service (QoS). One ormultiple service(s) or service component(s) can be carried by a singleDP. Details of operations of the input formatting block 1000 will bedescribed later.

The data pipe is represented to the data transmission (or transport)channel or the PLP.

The data pipe is a logical channel in the physical layer that carriesservice data or related metadata, which may carry one or multipleservice(s) or service component(s).

The data pipe can be represented to a data transmission channel.

Also, the data pipe unit: a basic unit for allocating data cells to a DPin a frame.

In the BICM block 1010, parity data is added for error correction andthe encoded bit streams are mapped to complex-value constellationsymbols. The symbols are interleaved across a specific interleavingdepth that is used for the corresponding DP. For the advanced profile,MIMO encoding is performed in the BICM block 1010 and the additionaldata path is added at the output for MIMO transmission. Details ofoperations of the BICM block 1010 will be described later.

The Input Formatting Block of FIG. 1 implements functions, processes,and/or methods proposed in FIGS. 50, 51, and 52 to be described below.

The Frame Building block 1020 can map the data cells of the input DPsinto the OFDM symbols within a frame. After mapping, the frequencyinterleaving is used for frequency-domain diversity, especially tocombat frequency-selective fading channels. Details of operations of theFrame Building block 1020 will be described later.

After inserting a preamble at the beginning of each frame, the OFDMGeneration block 1030 can apply conventional OFDM modulation having acyclic prefix as guard interval. For antenna space diversity, adistributed MISO scheme is applied across the transmitters. In addition,a Peak-to-Average Power Reduction (PAPR) scheme is performed in the timedomain. For flexible network planning, this proposal provides a set ofvarious FFT sizes, guard interval lengths and corresponding pilotpatterns. Details of operations of the OFDM Generation block 1030 willbe described later.

The Signaling Generation block 1040 can create physical layer signalinginformation used for the operation of each functional block. Thissignaling information is also transmitted so that the services ofinterest are properly recovered at the receiver side. Details ofoperations of the Signaling Generation block 1040 will be describedlater.

FIGS. 2, 3 and 4 illustrate the input formatting block 1000 according toembodiments of the present invention. A description will be given ofeach figure.

The Input Formatting Block of FIG. 2 to FIG. 4 implements functions,processes, and/or methods proposed in FIGS. 50, 51, and 52 to bedescribed below.

FIG. 2 illustrates an input formatting block according to one embodimentof the present invention. FIG. 2 shows an input formatting module whenthe input signal is a single input stream.

The input formatting block illustrated in FIG. 2 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

The input to the physical layer may be composed of one or multiple datastreams. Each data stream is carried by one DP. The mode adaptationmodules slice the incoming data stream into data fields of the basebandframe (BBF). The system supports three types of input data streams:MPEG2-TS, Internet protocol (IP) and Generic stream (GS). MPEG2-TS ischaracterized by fixed length (188 byte) packets with the first bytebeing a sync-byte (0x47). An IP stream is composed of variable length IPdatagram packets, as signaled within IP packet headers. The systemsupports both IPv4 and IPv6 for the IP stream. GS may be composed ofvariable length packets or constant length packets, signaled withinencapsulation packet headers.

(a) shows a mode adaptation block 2000 and a stream adaptation 2010 forsignal DP and (b) shows a PLS generation block 2020 and a PLS scrambler2030 for generating and processing PLS data. A description will be givenof the operation of each block.

The Input Stream Splitter splits the input TS, IP, GS streams intomultiple service or service component (audio, video, etc.) streams. Themode adaptation module 2010 is comprised of a CRC Encoder, BB (baseband)Frame Slicer, and BB Frame Header Insertion block.

The CRC Encoder provides three kinds of CRC encoding for error detectionat the user packet (UP) level, i.e., CRC-8, CRC-16, and CRC-32. Thecomputed CRC bytes are appended after the UP. CRC-8 is used for TSstream and CRC-32 for IP stream. If the GS stream doesn't provide theCRC encoding, the proposed CRC encoding should be applied.

BB Frame Slicer maps the input into an internal logical-bit format. Thefirst received bit is defined to be the MSB. The BB Frame Slicerallocates a number of input bits equal to the available data fieldcapacity. To allocate a number of input bits equal to the BBF payload,the UP packet stream is sliced to fit the data field of BBF.

BB Frame Header Insertion block can insert fixed length BBF header of 2bytes is inserted in front of the BB Frame. The BBF header is composedof STUFFI (1 bit), SYNCD (13 bits), and RFU (2 bits). In addition to thefixed 2-Byte BBF header, BBF can have an extension field (1 or 3 bytes)at the end of the 2-byte BBF header.

The stream adaptation 2010 is comprised of stuffing insertion block andBB scrambler.

The stuffing insertion block can insert stuffing field into a payload ofa BB frame. If the input data to the stream adaptation is sufficient tofill a BB-Frame, STUFFI is set to ‘0’ and the BBF has no stuffing field.Otherwise STUFFI is set to ‘1’ and the stuffing field is insertedimmediately after the BBF header. The stuffing field comprises two bytesof the stuffing field header and a variable size of stuffing data.

The BB scrambler scrambles complete BBF for energy dispersal. Thescrambling sequence is synchronous with the BBF. The scrambling sequenceis generated by the feed-back shift register.

The PLS generation block 2020 can generate physical layer signaling(PLS) data. The PLS provides the receiver with a means to accessphysical layer DPs. The PLS data consists of PLS1 data and PLS2 data.

The PLS1 data is a first set of PLS data carried in the FSS symbols inthe frame having a fixed size, coding and modulation, which carriesbasic information about the system as well as the parameters needed todecode the PLS2 data. The PLS1 data provides basic transmissionparameters including parameters required to enable the reception anddecoding of the PLS2 data. Also, the PLS1 data remains constant for theduration of a frame-group.

The PLS2 data is a second set of PLS data transmitted in the FSS symbol,which carries more detailed PLS data about the system and the DPs. ThePLS2 contains parameters that provide sufficient information for thereceiver to decode the desired DP. The PLS2 signaling further consistsof two types of parameters, PLS2 Static data (PLS2-STAT data) and PLS2dynamic data (PLS2-DYN data). The PLS2 Static data is PLS2 data thatremains static for the duration of a frame-group and the PLS2 dynamicdata is PLS2 data that may dynamically change frame-by-frame.

Details of the PLS data will be described later.

The PLS scrambler 2030 can scramble the generated PLS data for energydispersal.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 3 illustrates an input formatting block according to anotherembodiment of the present invention.

The input formatting block illustrated in FIG. 3 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

FIG. 3 shows a mode adaptation block of the input formatting block whenthe input signal corresponds to multiple input streams.

The mode adaptation block of the input formatting block for processingthe multiple input streams can independently process the multiple inputstreams.

Referring to FIG. 3, the mode adaptation block for respectivelyprocessing the multiple input streams can include an input streamsplitter 3000, an input stream synchronizer 3010, a compensating delayblock 3020, a null packet deletion block 3030, a head compression block3040, a CRC encoder 3050, a BB frame slicer 3060 and a BB headerinsertion block 3070. Description will be given of each block of themode adaptation block.

Operations of the CRC encoder 3050, BB frame slicer 3060 and BB headerinsertion block 3070 correspond to those of the CRC encoder, BB frameslicer and BB header insertion block described with reference to FIG. 2and thus description thereof is omitted.

The input stream splitter 3000 can split the input TS, IP, GS streamsinto multiple service or service component (audio, video, etc.) streams.

The input stream synchronizer 3010 may be referred as ISSY. The ISSY canprovide suitable means to guarantee Constant Bit Rate (CBR) and constantend-to-end transmission delay for any input data format. The ISSY isalways used for the case of multiple DPs carrying TS, and optionallyused for multiple DPs carrying GS streams.

The compensating delay block 3020 can delay the split TS packet streamfollowing the insertion of ISSY information to allow a TS packetrecombining mechanism without requiring additional memory in thereceiver.

The null packet deletion block 3030, is used only for the TS inputstream case. Some TS input streams or split TS streams may have a largenumber of null-packets present in order to accommodate VBR (variablebit-rate) services in a CBR TS stream. In this case, in order to avoidunnecessary transmission overhead, null-packets can be identified andnot transmitted. In the receiver, removed null-packets can bere-inserted in the exact place where they were originally by referenceto a deleted null-packet (DNP) counter that is inserted in thetransmission, thus guaranteeing constant bit-rate and avoiding the needfor time-stamp (PCR) updating.

The head compression block 3040 can provide packet header compression toincrease transmission efficiency for TS or IP input streams. Because thereceiver can have a priori information on certain parts of the header,this known information can be deleted in the transmitter.

For Transport Stream, the receiver has a-priori information about thesync-byte configuration (0x47) and the packet length (188 Byte). If theinput TS stream carries content that has only one PID, i.e., for onlyone service component (video, audio, etc.) or service sub-component (SVCbase layer, SVC enhancement layer, MVC base view or MVC dependentviews), TS packet header compression can be applied (optionally) to theTransport Stream. IP packet header compression is used optionally if theinput steam is an IP stream.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 4 illustrates an input formatting block according to anotherembodiment of the present invention.

The input formatting block illustrated in FIG. 4 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

FIG. 4 illustrates a stream adaptation block of the input formattingmodule when the input signal corresponds to multiple input streams.

Referring to FIG. 4, the mode adaptation block for respectivelyprocessing the multiple input streams can include a scheduler 4000, an1-Frame delay block 4010, a stuffing insertion block 4020, an in-bandsignaling 4030, a BB Frame scrambler 4040, a PLS generation block 4050and a PLS scrambler 4060. Description will be given of each block of thestream adaptation block.

Operations of the stuffing insertion block 4020, the BB Frame scrambler4040, the PLS generation block 4050 and the PLS scrambler 4060correspond to those of the stuffing insertion block, BB scrambler, PLSgeneration block and the PLS scrambler described with reference to FIG.2 and thus description thereof is omitted.

The scheduler 4000 can determine the overall cell allocation across theentire frame from the amount of FECBLOCKs of each DP. Including theallocation for PLS, EAC and FIC, the scheduler generate the values ofPLS2-DYN data, which is transmitted as in-band signaling or PLS cell inFSS of the frame. Details of FECBLOCK, EAC and FIC will be describedlater.

The 1-Frame delay block 4010 can delay the input data by onetransmission frame such that scheduling information about the next framecan be transmitted through the current frame for in-band signalinginformation to be inserted into the DPs.

The in-band signaling 4030 can insert un-delayed part of the PLS2 datainto a DP of a frame.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 5 illustrates a BICM block according to an embodiment of thepresent invention.

The BICM block illustrated in FIG. 5 corresponds to an embodiment of theBICM block 1010 described with reference to FIG. 1.

As described above, the apparatus for transmitting broadcast signals forfuture broadcast services according to an embodiment of the presentinvention can provide a terrestrial broadcast service, mobile broadcastservice, UHDTV service, etc.

Since QoS (quality of service) depends on characteristics of a serviceprovided by the apparatus for transmitting broadcast signals for futurebroadcast services according to an embodiment of the present invention,data corresponding to respective services needs to be processed throughdifferent schemes. Accordingly, the a BICM block according to anembodiment of the present invention can independently process DPs inputthereto by independently applying SISO, MISO and MIMO schemes to thedata pipes respectively corresponding to data paths. Consequently, theapparatus for transmitting broadcast signals for future broadcastservices according to an embodiment of the present invention can controlQoS for each service or service component transmitted through each DP.

(a) shows the BICM block shared by the base profile and the handheldprofile and (b) shows the BICM block of the advanced profile.

The BICM block shared by the base profile and the handheld profile andthe BICM block of the advanced profile can include plural processingblocks for processing each DP.

A description will be given of each processing block of the BICM blockfor the base profile and the handheld profile and the BICM block for theadvanced profile.

A processing block 5000 of the BICM block for the base profile and thehandheld profile can include a Data FEC encoder 5010, a bit interleaver5020, a constellation mapper 5030, an SSD (Signal Space Diversity)encoding block 5040 and a time interleaver 5050.

The Data FEC encoder 5010 can perform the FEC encoding on the input BBFto generate FECBLOCK procedure using outer coding (BCH), and innercoding (LDPC). The outer coding (BCH) is optional coding method. Detailsof operations of the Data FEC encoder 5010 will be described later.

The bit interleaver 5020 can interleave outputs of the Data FEC encoder5010 to achieve optimized performance with combination of the LDPC codesand modulation scheme while providing an efficiently implementablestructure. Details of operations of the bit interleaver 5020 will bedescribed later.

The constellation mapper 5030 can modulate each cell word from the bitinterleaver 5020 in the base and the handheld profiles, or cell wordfrom the Cell-word demultiplexer 5010-1 in the advanced profile usingeither QPSK, QAM-16, non-uniform QAM (NUQ-64, NUQ-256, NUQ-1024) ornon-uniform constellation (NUC-16, NUC-64, NUC-256, NUC-1024) to give apower-normalized constellation point, el. This constellation mapping isapplied only for DPs. Observe that QAM-16 and NUQs are square shaped,while NUCs have arbitrary shape. When each constellation is rotated byany multiple of 90 degrees, the rotated constellation exactly overlapswith its original one. This “rotation-sense” symmetric property makesthe capacities and the average powers of the real and imaginarycomponents equal to each other. Both NUQs and NUCs are definedspecifically for each code rate and the particular one used is signaledby the parameter DP_MOD filed in PLS2 data.

The SSD encoding block 5040 can precode cells in two (2D), three (3D),and four (4D) dimensions to increase the reception robustness underdifficult fading conditions.

The time interleaver 5050 can operates at the DP level. The parametersof time interleaving (TI) may be set differently for each DP. Details ofoperations of the time interleaver 5050 will be described later.

A processing block 5000-1 of the BICM block for the advanced profile caninclude the Data FEC encoder, bit interleaver, constellation mapper, andtime interleaver. However, the processing block 5000-1 is distinguishedfrom the processing block 5000 further includes a cell-worddemultiplexer 5010-1 and a MIMO encoding block 5020-1.

Also, the operations of the Data FEC encoder, bit interleaver,constellation mapper, and time interleaver in the processing block5000-1 correspond to those of the Data FEC encoder 5010, bit interleaver5020, constellation mapper 5030, and time interleaver 5050 described andthus description thereof is omitted.

The cell-word demultiplexer 5010-1 is used for the DP of the advancedprofile to divide the single cell-word stream into dual cell-wordstreams for MIMO processing. Details of operations of the cell-worddemultiplexer 5010-1 will be described later.

The MIMO encoding block 5020-1 can processing the output of thecell-word demultiplexer 5010-1 using MIMO encoding scheme. The MIMOencoding scheme was optimized for broadcasting signal transmission. TheMIMO technology is a promising way to get a capacity increase but itdepends on channel characteristics. Especially for broadcasting, thestrong LOS component of the channel or a difference in the receivedsignal power between two antennas caused by different signal propagationcharacteristics makes it difficult to get capacity gain from MIMO. Theproposed MIMO encoding scheme overcomes this problem using arotation-based pre-coding and phase randomization of one of the MIMOoutput signals.

MIMO encoding is intended for a 2×2 MIMO system requiring at least twoantennas at both the transmitter and the receiver. Two MIMO encodingmodes are defined in this proposal; full-rate spatial multiplexing(FR-SM) and full-rate full-diversity spatial multiplexing (FRFD-SM). TheFR-SM encoding provides capacity increase with relatively smallcomplexity increase at the receiver side while the FRFD-SM encodingprovides capacity increase and additional diversity gain with a greatcomplexity increase at the receiver side. The proposed MIMO encodingscheme has no restriction on the antenna polarity configuration.

MIMO processing is required for the advanced profile frame, which meansall DPs in the advanced profile frame are processed by the MIMO encoder.MIMO processing is applied at DP level. Pairs of the ConstellationMapper outputs NUQ (e1,i and e2,i) are fed to the input of the MIMOEncoder. Paired MIMO Encoder output (g1,i and g2,i) is transmitted bythe same carrier k and OFDM symbol 1 of their respective TX antennas.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 6 illustrates a BICM block according to another embodiment of thepresent invention.

The BICM block illustrated in FIG. 6 corresponds to an embodiment of theBICM block 1010 described with reference to FIG. 1.

FIG. 6 illustrates a BICM block for protection of physical layersignaling (PLS), emergency alert channel (EAC) and fast informationchannel (FIC). EAC is a part of a frame that carries EAS informationdata and FIC is a logical channel in a frame that carries the mappinginformation between a service and the corresponding base DP. Details ofthe EAC and FIC will be described later.

Referring to FIG. 6, the BICM block for protection of PLS, EAC and FICcan include a PLS FEC encoder 6000, a bit interleaver 6010, aconstellation mapper 6020 and time interleaver 6030.

Also, the PLS FEC encoder 6000 can include a scrambler, BCHencoding/zero insertion block, LDPC encoding block and LDPC paritypunturing block. Description will be given of each block of the BICMblock.

The PLS FEC encoder 6000 can encode the scrambled PLS 1/2 data, EAC andFIC section.

The scrambler can scramble PLS1 data and PLS2 data before BCH encodingand shortened and punctured LDPC encoding.

The BCH encoding/zero insertion block can perform outer encoding on thescrambled PLS 1/2 data using the shortened BCH code for PLS protectionand insert zero bits after the BCH encoding. For PLS1 data only, theoutput bits of the zero insertion may be permutted before LDPC encoding.

The LDPC encoding block can encode the output of the BCH encoding/zeroinsertion block using LDPC code. To generate a complete coded block,Cldpc, parity bits, Pldpc are encoded systematically from eachzero-inserted PLS information block, Ildpc and appended after it.

C _(ldpc) =[I _(ldpc) P _(ldpc) ]=[i ₀ ,i ₁ , . . . ,i _(K) _(ldpc) ⁻¹,p ₀ ,p ₁ , . . . ,p _(N) _(ldpc) _(−K) _(ldpc) ⁻¹]  [Math figure 1]

The LDPC code parameters for PLS1 and PLS2 are as following table 4.

TABLE 4 Signaling Kldpc code Type Ksig Kbch Nbch_parity (=Nbch) NldpcNldpc_parity rate Qldpc PLS1 342 1020 60 1080 4320 3240 1/4  36 PLS2<1021 >1020 2100 2160 7200 5040 3/10 56

The LDPC parity punturing block can perform puncturing on the PLS1 dataand PLS 2 data.

When shortening is applied to the PLS1 data protection, some LDPC paritybits are punctured after LDPC encoding. Also, for the PLS2 dataprotection, the LDPC parity bits of PLS2 are punctured after LDPCencoding. These punctured bits are not transmitted.

The bit interleaver 6010 can interleave the each shortened and puncturedPLS1 data and PLS2 data.

The constellation mapper 6020 can map the bit interleaved PLS1 data andPLS2 data onto constellations.

The time interleaver 6030 can interleave the mapped PLS1 data and PLS2data.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 7 illustrates a frame building block according to one embodiment ofthe present invention.

The frame building block illustrated in FIG. 7 corresponds to anembodiment of the frame building block 1020 described with reference toFIG. 1.

Referring to FIG. 7, the frame building block can include a delaycompensation block 7000, a cell mapper 7010 and a frequency interleaver7020. Description will be given of each block of the frame buildingblock.

The delay compensation block 7000 can adjust the timing between the datapipes and the corresponding PLS data to ensure that they are co-timed atthe transmitter end. The PLS data is delayed by the same amount as datapipes are by addressing the delays of data pipes caused by the InputFormatting block and BICM block. The delay of the BICM block is mainlydue to the time interleaver 5050. In-band signaling data carriesinformation of the next TI group so that they are carried one frameahead of the DPs to be signaled. The Delay Compensating block delaysin-band signaling data accordingly.

The cell mapper 7010 can map PLS, EAC, FIC, DPs, auxiliary streams anddummy cells into the active carriers of the OFDM symbols in the frame.The basic function of the cell mapper 7010 is to map data cells producedby the TIs for each of the DPs, PLS cells, and EAC/FIC cells, if any,into arrays of active OFDM cells corresponding to each of the OFDMsymbols within a frame. Service signaling data (such as PSI (programspecific information)/SI) can be separately gathered and sent by a datapipe. The Cell Mapper operates according to the dynamic informationproduced by the scheduler and the configuration of the frame structure.Details of the frame will be described later.

The frequency interleaver 7020 can randomly interleave data cellsreceived from the cell mapper 7010 to provide frequency diversity. Also,the frequency interleaver 7020 can operate on very OFDM symbol paircomprised of two sequential OFDM symbols using a differentinterleaving-seed order to get maximum interleaving gain in a singleframe. Details of operations of the frequency interleaver 7020 will bedescribed later.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 8 illustrates an OFMD generation block according to an embodimentof the present invention.

The OFMD generation block illustrated in FIG. 8 corresponds to anembodiment of the OFMD generation block 1030 described with reference toFIG. 1.

The OFDM generation block modulates the OFDM carriers by the cellsproduced by the Frame Building block, inserts the pilots, and producesthe time domain signal for transmission. Also, this block subsequentlyinserts guard intervals, and applies PAPR (Peak-to-Average Power Radio)reduction processing to produce the final RF signal.

Referring to FIG. 8, the frame building block can include a pilot andreserved tone insertion block 8000, a 2D-eSFN encoding block 8010, anIFFT (Inverse Fast Fourier Transform) block 8020, a PAPR reduction block8030, a guard interval insertion block 8040, a preamble insertion block8050, other system insertion block 8060 and a DAC block 8070.Description will be given of each block of the frame building block.

The pilot and reserved tone insertion block 8000 can insert pilots andthe reserved tone.

Various cells within the OFDM symbol are modulated with referenceinformation, known as pilots, which have transmitted values known apriori in the receiver. The information of pilot cells is made up ofscattered pilots, continual pilots, edge pilots, FSS (frame signalingsymbol) pilots and FES (frame edge symbol) pilots. Each pilot istransmitted at a particular boosted power level according to pilot typeand pilot pattern. The value of the pilot information is derived from areference sequence, which is a series of values, one for eachtransmitted carrier on any given symbol. The pilots can be used forframe synchronization, frequency synchronization, time synchronization,channel estimation, and transmission mode identification, and also canbe used to follow the phase noise.

Reference information, taken from the reference sequence, is transmittedin scattered pilot cells in every symbol except the preamble, FSS andFES of the frame. Continual pilots are inserted in every symbol of theframe. The number and location of continual pilots depends on both theFFT size and the scattered pilot pattern. The edge carriers are edgepilots in every symbol except for the preamble symbol. They are insertedin order to allow frequency interpolation up to the edge of thespectrum. FSS pilots are inserted in FSS(s) and FES pilots are insertedin FES. They are inserted in order to allow time interpolation up to theedge of the frame.

The system according to an embodiment of the present invention supportsthe SFN network, where distributed MISO scheme is optionally used tosupport very robust transmission mode. The 2D-eSFN is a distributed MISOscheme that uses multiple TX antennas, each of which is located in thedifferent transmitter site in the SFN network.

The 2D-eSFN encoding block 8010 can process a 2D-eSFN processing todistorts the phase of the signals transmitted from multipletransmitters, in order to create both time and frequency diversity inthe SFN configuration. Hence, burst errors due to low flat fading ordeep-fading for a long time can be mitigated.

The IFFT block 8020 can modulate the output from the 2D-eSFN encodingblock 8010 using OFDM modulation scheme. Any cell in the data symbolswhich has not been designated as a pilot (or as a reserved tone) carriesone of the data cells from the frequency interleaver. The cells aremapped to OFDM carriers.

The PAPR reduction block 8030 can perform a PAPR reduction on inputsignal using various PAPR reduction algorithm in the time domain.

The guard interval insertion block 8040 can insert guard intervals andthe preamble insertion block 8050 can insert preamble in front of thesignal. Details of a structure of the preamble will be described later.The other system insertion block 8060 can multiplex signals of aplurality of broadcast transmission/reception systems in the time domainsuch that data of two or more different broadcast transmission/receptionsystems providing broadcast services can be simultaneously transmittedin the same RF signal bandwidth. In this case, the two or more differentbroadcast transmission/reception systems refer to systems providingdifferent broadcast services. The different broadcast services may referto a terrestrial broadcast service, mobile broadcast service, etc. Datarelated to respective broadcast services can be transmitted throughdifferent frames.

The DAC block 8070 can convert an input digital signal into an analogsignal and output the analog signal. The signal output from the DACblock 7800 can be transmitted through multiple output antennas accordingto the physical layer profiles. A Tx antenna according to an embodimentof the present invention can have vertical or horizontal polarity.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions according to design.

FIG. 9 illustrates a structure of an apparatus for receiving broadcastsignals for future broadcast services according to an embodiment of thepresent invention.

The apparatus for receiving broadcast signals for future broadcastservices according to an embodiment of the present invention cancorrespond to the apparatus for transmitting broadcast signals forfuture broadcast services, described with reference to FIG. 1.

The apparatus for receiving broadcast signals for future broadcastservices according to an embodiment of the present invention can includea synchronization & demodulation module 9000, a frame parsing module9010, a demapping & decoding module 9020, an output processor 9030 and asignaling decoding module 9040. A description will be given of operationof each module of the apparatus for receiving broadcast signals.

The synchronization & demodulation module 9000 can be represented to areceiver and an OFDM demodulator.

The frame parsing module 9010 can be represented to a frame parser.

The frame parsing module is represented to a deframing & deinterleavingmodule (or block).

The demapping & decoding module 9020 can be represented to a converterand a decoder.

The synchronization & demodulation module 9000 can receive input signalsthrough m Rx antennas, perform signal detection and synchronization withrespect to a system corresponding to the apparatus for receivingbroadcast signals and carry out demodulation corresponding to a reverseprocedure of the procedure performed by the apparatus for transmittingbroadcast signals.

The frame parsing module 9100 can parse input signal frames and extractdata through which a service selected by a user is transmitted. If theapparatus for transmitting broadcast signals performs interleaving, theframe parsing module 9100 can carry out deinterleaving corresponding toa reverse procedure of interleaving. In this case, the positions of asignal and data that need to be extracted can be obtained by decodingdata output from the signaling decoding module 9400 to restorescheduling information generated by the apparatus for transmittingbroadcast signals.

The demapping & decoding module 9200 can convert the input signals intobit domain data and then deinterleave the same as necessary. Thedemapping & decoding module 9200 can perform demapping for mappingapplied for transmission efficiency and correct an error generated on atransmission channel through decoding. In this case, the demapping &decoding module 9200 can obtain transmission parameters necessary fordemapping and decoding by decoding the data output from the signalingdecoding module 9400.

The output processor 9300 can perform reverse procedures of variouscompression/signal processing procedures which are applied by theapparatus for transmitting broadcast signals to improve transmissionefficiency. In this case, the output processor 9300 can acquirenecessary control information from data output from the signalingdecoding module 9400. The output of the output processor 8300corresponds to a signal input to the apparatus for transmittingbroadcast signals and may be MPEG-TSs, IP streams (v4 or v6) and genericstreams.

The signaling decoding module 9400 can obtain PLS information from thesignal demodulated by the synchronization & demodulation module 9000. Asdescribed above, the frame parsing module 9100, demapping & decodingmodule 9200 and output processor 9300 can execute functions thereofusing the data output from the signaling decoding module 9400.

The Output Processor of FIG. 9 implements functions, processes, and/ormethods proposed in FIGS. 50, 51, and 53 to be described below.

FIG. 10 illustrates a frame structure according to an embodiment of thepresent invention.

FIG. 10 shows an example configuration of the frame types and FRUs in asuper-frame. (a) shows a super frame according to an embodiment of thepresent invention, (b) shows FRU (Frame Repetition Unit) according to anembodiment of the present invention, (c) shows frames of variable PHYprofiles in the FRU and (d) shows a structure of a frame.

A super-frame may be composed of eight FRUs. The FRU is a basicmultiplexing unit for TDM of the frames, and is repeated eight times ina super-frame.

Each frame in the FRU belongs to one of the PHY profiles, (base,handheld, advanced) or FEF. The maximum allowed number of the frames inthe FRU is four and a given PHY profile can appear any number of timesfrom zero times to four times in the FRU (e.g., base, base, handheld,advanced). PHY profile definitions can be extended using reserved valuesof the PHY_PROFILE in the preamble, if required.

The FEF part is inserted at the end of the FRU, if included. When theFEF is included in the FRU, the minimum number of FEFs is 8 in asuper-frame. It is not recommended that FEF parts be adjacent to eachother.

One frame is further divided into a number of OFDM symbols and apreamble. As shown in (d), the frame comprises a preamble, one or moreframe signaling symbols (FSS), normal data symbols and a frame edgesymbol (FES).

The preamble is a special symbol that enables fast Futurecast UTB systemsignal detection and provides a set of basic transmission parameters forefficient transmission and reception of the signal. The detaileddescription of the preamble will be will be described later.

The main purpose of the FSS(s) is to carry the PLS data. For fastsynchronization and channel estimation, and hence fast decoding of PLSdata, the FSS has more dense pilot pattern than the normal data symbol.The FES has exactly the same pilots as the FSS, which enablesfrequency-only interpolation within the FES and temporal interpolation,without extrapolation, for symbols immediately preceding the FES.

FIG. 11 illustrates a signaling hierarchy structure of the frameaccording to an embodiment of the present invention.

FIG. 11 illustrates the signaling hierarchy structure, which is splitinto three main parts: the preamble signaling data 11000, the PLS1 data11010 and the PLS2 data 11020. The purpose of the preamble, which iscarried by the preamble symbol in every frame, is to indicate thetransmission type and basic transmission parameters of that frame. ThePLS1 enables the receiver to access and decode the PLS2 data, whichcontains the parameters to access the DP of interest. The PLS2 iscarried in every frame and split into two main parts: PLS2-STAT data andPLS2-DYN data. The static and dynamic portion of PLS2 data is followedby padding, if necessary.

FIG. 12 illustrates preamble signaling data according to an embodimentof the present invention.

Preamble signaling data carries 21 bits of information that are neededto enable the receiver to access PLS data and trace DPs within the framestructure. Details of the preamble signaling data are as follows:

PHY_PROFILE: This 3-bit field indicates the PHY profile type of thecurrent frame. The mapping of different PHY profile types is given inbelow table 5.

TABLE 5 Value PHY profile 000 Base profile 001 Handheld profile 010Advanced profiled 011~110 Reserved 111 FEF

FFT_SIZE: This 2 bit field indicates the FFT size of the current framewithin a frame-group, as described in below table 6.

TABLE 6 Value FFT size 00  8K FFT 01 16K FFT 10 32K FFT 11 Reserved

GI_FRACTION: This 3 bit field indicates the guard interval fractionvalue in the current super-frame, as described in below table 7.

TABLE 7 Value GI_FRACTION 000 ⅕ 001 1/10 010 1/20 011 1/40 100 1/80 1011/160 110~111 Reserved

EAC_FLAG: This 1 bit field indicates whether the EAC is provided in thecurrent frame. If this field is set to ‘1’, emergency alert service(EAS) is provided in the current frame. If this field set to ‘0’, EAS isnot carried in the current frame. This field can be switched dynamicallywithin a super-frame.

PILOT_MODE: This 1-bit field indicates whether the pilot mode is mobilemode or fixed mode for the current frame in the current frame-group. Ifthis field is set to ‘0’, mobile pilot mode is used. If the field is setto ‘1’, the fixed pilot mode is used.

PAPR_FLAG: This 1-bit field indicates whether PAPR reduction is used forthe current frame in the current frame-group. If this field is set tovalue ‘1’, tone reservation is used for PAPR reduction. If this field isset to ‘0’, PAPR reduction is not used.

FRU_CONFIGURE: This 3-bit field indicates the PHY profile typeconfigurations of the frame repetition units (FRU) that are present inthe current super-frame. All profile types conveyed in the currentsuper-frame are identified in this field in all preambles in the currentsuper-frame. The 3-bit field has a different definition for eachprofile, as show in below table 8.

TABLE 8 Current Current Current Current PHY_PROFILE = PHY_PROFILE =PHY_PROFILE = PHY_PROFILE = ‘000’ ‘001’ ‘010’ ‘111’ (base) (handheld)(advanced) (FEF) FRU_CONFIGURE = Only base Only Only Only FEF 000profile handheld advanced present present profile profile presentpresent FRU_CONFIGURE = Handheld Base Base Base 1XX profile profileprofile profile present present present present FRU_CONFIGURE = AdvancedAdvanced Handheld Handheld X1X profile profile profile profile presentpresent present present FRU_CONFIGURE = FEF FEF FEF Advanced XX1 presentpresent present profile present

RESERVED: This 7-bit field is reserved for future use.

FIG. 13 illustrates PLS1 data according to an embodiment of the presentinvention.

PLS1 data provides basic transmission parameters including parametersrequired to enable the reception and decoding of the PLS2. As abovementioned, the PLS1 data remain unchanged for the entire duration of oneframe-group. The detailed definition of the signaling fields of the PLS1data are as follows:

PREAMBLE_DATA: This 20-bit field is a copy of the preamble signalingdata excluding the EAC_FLAG.

NUM_FRAME_FRU: This 2-bit field indicates the number of the frames perFRU.

PAYLOAD_TYPE: This 3-bit field indicates the format of the payload datacarried in the frame-group. PAYLOAD_TYPE is signaled as shown in table9.

TABLE 9 Value Payload type 1XX TS stream is transmitted X1X IP stream istransmitted XX1 GS stream is transmitted

NUM_FSS: This 2-bit field indicates the number of FSS symbols in thecurrent frame.

SYSTEM_VERSION: This 8-bit field indicates the version of thetransmitted signal format. The SYSTEM_VERSION is divided into two 4-bitfields, which are a major version and a minor version.

Major version: The MSB four bits of SYSTEM_VERSION field indicate majorversion information. A change in the major version field indicates anon-backward-compatible change. The default value is ‘0000’. For theversion described in this standard, the value is set to ‘0000’.

Minor version: The LSB four bits of SYSTEM_VERSION field indicate minorversion information. A change in the minor version field isbackward-compatible.

CELL_ID: This is a 16-bit field which uniquely identifies a geographiccell in an ATSC network. An ATSC cell coverage area may consist of oneor more frequencies, depending on the number of frequencies used perFuturecast UTB system. If the value of the CELL_ID is not known orunspecified, this field is set to ‘0’.

NETWORK_ID: This is a 16-bit field which uniquely identifies the currentATSC network.

SYSTEM_ID: This 16-bit field uniquely identifies the Futurecast UTBsystem within the ATSC network. The Futurecast UTB system is theterrestrial broadcast system whose input is one or more input streams(TS, IP, GS) and whose output is an RF signal. The Futurecast UTB systemcarries one or more PHY profiles and FEF, if any. The same FuturecastUTB system may carry different input streams and use different RFfrequencies in different geographical areas, allowing local serviceinsertion. The frame structure and scheduling is controlled in one placeand is identical for all transmissions within a Futurecast UTB system.One or more Futurecast UTB systems may have the same SYSTEM_ID meaningthat they all have the same physical layer structure and configuration.

The following loop consists of FRU_PHY_PROFILE, FRU_FRAME_LENGTH,FRU_GI_FRACTION, and RESERVED which are used to indicate the FRUconfiguration and the length of each frame type. The loop size is fixedso that four PHY profiles (including a FEF) are signaled within the FRU.If NUM_FRAME_FRU is less than 4, the unused fields are filled withzeros.

FRU_PHY_PROFILE: This 3-bit field indicates the PHY profile type of the(i+1)th (i is the loop index) frame of the associated FRU. This fielduses the same signaling format as shown in the table 8.

FRU_FRAME_LENGTH: This 2-bit field indicates the length of the (i+1)thframe of the associated FRU. Using FRU_FRAME_LENGTH together withFRU_GI_FRACTION, the exact value of the frame duration can be obtained.

FRU_GI_FRACTION: This 3-bit field indicates the guard interval fractionvalue of the (i+1)th frame of the associated FRU. FRU_GI_FRACTION issignaled according to the table 7.

RESERVED: This 4-bit field is reserved for future use.

The following fields provide parameters for decoding the PLS2 data.

PLS2_FEC_TYPE: This 2-bit field indicates the FEC type used by the PLS2protection. The FEC type is signaled according to table 10. The detailsof the LDPC codes will be described later.

TABLE 10 Contents PLS2 FEC type 00 4K-1/4 and 7K-3/10 LDPC codes 01~11Reserved

PLS2_MOD: This 3-bit field indicates the modulation type used by thePLS2. The modulation type is signaled according to table 11.

TABLE 11 Value PLS2_MODE 000 BPSK 001 QPSK 010 QAM-16 011 NUQ-64 100~111Reserved

PLS2_SIZE_CELL: This 15-bit field indicates Ctotal_partial_block, thesize (specified as the number of QAM cells) of the collection of fullcoded blocks for PLS2 that is carried in the current frame-group. Thisvalue is constant during the entire duration of the current frame-group.

PLS2_STAT_SIZE_BIT: This 14-bit field indicates the size, in bits, ofthe PLS2-STAT for the current frame-group. This value is constant duringthe entire duration of the current frame-group.

PLS2_DYN_SIZE_BIT: This 14-bit field indicates the size, in bits, of thePLS2-DYN for the current frame-group. This value is constant during theentire duration of the current frame-group.

PLS2_REP_FLAG: This 1-bit flag indicates whether the PLS2 repetitionmode is used in the current frame-group. When this field is set to value‘1’, the PLS2 repetition mode is activated. When this field is set tovalue ‘0’, the PLS2 repetition mode is deactivated.

PLS2_REP_SIZE_CELL: This 15-bit field indicates Ctotal_partial_block,the size (specified as the number of QAM cells) of the collection ofpartial coded blocks for PLS2 carried in every frame of the currentframe-group, when PLS2 repetition is used. If repetition is not used,the value of this field is equal to 0. This value is constant during theentire duration of the current frame-group.

PLS2_NEXT_FEC_TYPE: This 2-bit field indicates the FEC type used forPLS2 that is carried in every frame of the next frame-group. The FECtype is signaled according to the table 10.

PLS2_NEXT_MOD: This 3-bit field indicates the modulation type used forPLS2 that is carried in every frame of the next frame-group. Themodulation type is signaled according to the table 11.

PLS2_NEXT_REP_FLAG: This 1-bit flag indicates whether the PLS2repetition mode is used in the next frame-group. When this field is setto value ‘1’, the PLS2 repetition mode is activated. When this field isset to value ‘0’, the PLS2 repetition mode is deactivated.

PLS2_NEXT_REP_SIZE_CELL: This 15-bit field indicates Ctotal_full_block,The size (specified as the number of QAM cells) of the collection offull coded blocks for PLS2 that is carried in every frame of the nextframe-group, when PLS2 repetition is used. If repetition is not used inthe next frame-group, the value of this field is equal to 0. This valueis constant during the entire duration of the current frame-group.

PLS2_NEXT_REP_STAT_SIZE_BIT: This 14-bit field indicates the size, inbits, of the PLS2-STAT for the next frame-group. This value is constantin the current frame-group.

PLS2_NEXT_REP_DYN_SIZE_BIT: This 14-bit field indicates the size, inbits, of the PLS2-DYN for the next frame-group. This value is constantin the current frame-group.

PLS2_AP_MODE: This 2-bit field indicates whether additional parity isprovided for PLS2 in the current frame-group. This value is constantduring the entire duration of the current frame-group. The below table12 gives the values of this field. When this field is set to ‘00’,additional parity is not used for the PLS2 in the current frame-group.

TABLE 12 Value PLS2-AP mode 00 AP is not provided 01 AP1 mode 10~11Reserved

PLS2_AP_SIZE_CELL: This 15-bit field indicates the size (specified asthe number of QAM cells) of the additional parity bits of the PLS2. Thisvalue is constant during the entire duration of the current frame-group.

PLS2_NEXT AP_MODE: This 2-bit field indicates whether additional parityis provided for PLS2 signaling in every frame of next frame-group. Thisvalue is constant during the entire duration of the current frame-group.The table 12 defines the values of this field

PLS2_NEXT AP_SIZE_CELL: This 15-bit field indicates the size (specifiedas the number of QAM cells) of the additional parity bits of the PLS2 inevery frame of the next frame-group. This value is constant during theentire duration of the current frame-group.

RESERVED: This 32-bit field is reserved for future use.

CRC_32: A 32-bit error detection code, which is applied to the entirePLS1 signaling.

FIG. 14 illustrates PLS2 data according to an embodiment of the presentinvention.

FIG. 14 illustrates PLS2-STAT data of the PLS2 data. The PLS2-STAT dataare the same within a frame-group, while the PLS2-DYN data provideinformation that is specific for the current frame.

The details of fields of the PLS2-STAT data are as follows:

FIC_FLAG: This 1-bit field indicates whether the FIC is used in thecurrent frame-group. If this field is set to ‘1’, the FIC is provided inthe current frame. If this field set to ‘0’, the FIC is not carried inthe current frame. This value is constant during the entire duration ofthe current frame-group.

AUX_FLAG: This 1-bit field indicates whether the auxiliary stream(s) isused in the current frame-group. If this field is set to ‘1’, theauxiliary stream is provided in the current frame. If this field set to‘0’, the auxiliary stream is not carried in the current frame. Thisvalue is constant during the entire duration of current frame-group.

NUM_DP: This 6-bit field indicates the number of DPs carried within thecurrent frame. The value of this field ranges from 1 to 64, and thenumber of DPs is NUM_DP+1.

DP_ID: This 6-bit field identifies uniquely a DP within a PHY profile.

DP_TYPE: This 3-bit field indicates the type of the DP. This is signaledaccording to the below table 13.

TABLE 13 Value DP Type 000 DP Type 1 001 DP Type 2 010~111 reserved

DP_GROUP_ID: This 8-bit field identifies the DP group with which thecurrent DP is associated. This can be used by a receiver to access theDPs of the service components associated with a particular service,which will have the same DP_GROUP_ID.

BASE_DP_ID: This 6-bit field indicates the DP carrying service signalingdata (such as PSI/SI) used in the Management layer. The DP indicated byBASE_DP_ID may be either a normal DP carrying the service signaling dataalong with the service data or a dedicated DP carrying only the servicesignaling data

DP_FEC_TYPE: This 2-bit field indicates the FEC type used by theassociated DP. The FEC type is signaled according to the below table 14.

TABLE 14 Value FEC_TYPE 00 16K LDPC 01 64K LDPC 10~11 Reserved

DP_COD: This 4-bit field indicates the code rate used by the associatedDP. The code rate is signaled according to the below table 15.

TABLE 15 Value Code rate 0000 5/15 0001 6/15 0010 7/15 0011 8/15 01009/15 0101 10/15  0110 11/15  0111 12/15  1000 13/15  1001~1111 Reserved

DP_MOD: This 4-bit field indicates the modulation used by the associatedDP. The modulation is signaled according to the below table 16.

TABLE 16 Value Modulation 0000 QPSK 0001 QAM-16 0010 NUQ-64 0011 NUQ-2560100 NUQ-1024 0101 NUC-16 0110 NUC-64 0111 NUC-256 1000 NUC-10241001~1111 reserved

DP_SSD_FLAG: This 1-bit field indicates whether the SSD mode is used inthe associated DP. If this field is set to value ‘1’, SSD is used. Ifthis field is set to value ‘0’, SSD is not used.

The following field appears only if PHY_PROFILE is equal to ‘010’, whichindicates the advanced profile:

DP_MIMO: This 3-bit field indicates which type of MIMO encoding processis applied to the associated DP. The type of MIMO encoding process issignaled according to the table 17.

TABLE 17 Value MIMO encoding 000 FR-SM 001 FRFD-SM 010~111 reserved

DP_TI_TYPE: This 1-bit field indicates the type of time-interleaving. Avalue of ‘0’ indicates that one TI group corresponds to one frame andcontains one or more TI-blocks. A value of ‘1’ indicates that one TIgroup is carried in more than one frame and contains only one TI-block.

DP_TI_LENGTH: The use of this 2-bit field (the allowed values are only1, 2, 4, 8) is determined by the values set within the DP_TI_TYPE fieldas follows:

If the DP_TI_TYPE is set to the value ‘1’, this field indicates PI, thenumber of the frames to which each TI group is mapped, and there is oneTI-block per TI group (NTI=1). The allowed PI values with 2-bit fieldare defined in the below table 18.

If the DP_TI_TYPE is set to the value ‘0’, this field indicates thenumber of TI-blocks NTI per TI group, and there is one TI group perframe (PI=1). The allowed PI values with 2-bit field are defined in thebelow table 18.

TABLE 18 2-bit field PI NTI 00 1 1 01 2 2 10 4 3 11 8 4

DP_FRAME_INTERVAL: This 2-bit field indicates the frame interval (IJUMP)within the frame-group for the associated DP and the allowed values are1, 2, 4, 8 (the corresponding 2-bit field is ‘00’, ‘01’, ‘10’, or ‘11’,respectively). For DPs that do not appear every frame of theframe-group, the value of this field is equal to the interval betweensuccessive frames. For example, if a DP appears on the frames 1, 5, 9,13, etc., this field is set to ‘4’. For DPs that appear in every frame,this field is set to ‘1’.

DP_TI_BYPASS: This 1-bit field determines the availability of timeinterleaver 5050. If time interleaving is not used for a DP, it is setto ‘1’. Whereas if time interleaving is used it is set to ‘0’.

DP_FIRST_FRAME_IDX: This 5-bit field indicates the index of the firstframe of the super-frame in which the current DP occurs. The value ofDP_FIRST_FRAME_IDX ranges from 0 to 31

DP_NUM_BLOCK_MAX: This 10-bit field indicates the maximum value ofDP_NUM_BLOCKS for this DP. The value of this field has the same range asDP_NUM_BLOCKS.

DP_PAYLOAD_TYPE: This 2-bit field indicates the type of the payload datacarried by the given DP. DP_PAYLOAD_TYPE is signaled according to thebelow table 19.

TABLE 19 Value Payload Type 00 TS. 01 IP 10 GS 11 reserved

DP_INBAND_MODE: This 2-bit field indicates whether the current DPcarries in-band signaling information. The in-band signaling type issignaled according to the below table 20.

TABLE 20 Value In-band mode 00 In-band signaling is not carried. 01INBAND-PLS is carried only 10 INBAND-ISSY is carried only 11 INBAND-PLSand INBAND-ISSY are carried

DP_PROTOCOL_TYPE: This 2-bit field indicates the protocol type of thepayload carried by the given DP. It is signaled according to the belowtable 21 when input payload types are selected.

TABLE 21 If If If DP_PAYLOAD_TYPE DP_PAYLOAD_TYPE DP_PAYLOAD_TYPE ValueIs TS Is IP Is GS 00 MPEG2-TS IPv4 (Note) 01 Reserved IPv6 Reserved 10Reserved Reserved Reserved 11 Reserved Reserved Reserved

DP_CRC_MODE: This 2-bit field indicates whether CRC encoding is used inthe Input Formatting block. The CRC mode is signaled according to thebelow table 22.

TABLE 22 Value CRC mode 00 Not used 01 CRC-8 10 CRC-16 11 CRC-32

DNP_MODE: This 2-bit field indicates the null-packet deletion mode usedby the associated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). DNP_MODEis signaled according to the below table 23. If DP_PAYLOAD_TYPE is notTS (‘00’), DNP_MODE is set to the value ‘00’.

TABLE 23 Value Null-packet deletion mode 00 Not used 01 DNP-NORMAL 10DNP-OFFSET 11 reserved

ISSY_MODE: This 2-bit field indicates the ISSY mode used by theassociated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). The ISSY_MODE issignaled according to the below table 24 If DP_PAYLOAD_TYPE is not TS(‘00’), ISSY_MODE is set to the value ‘00’.

TABLE 24 Value ISSY mode 00 Not used 01 ISSY-UP 10 ISSY-BBF 11 reserved

HC_MODE_TS: This 2-bit field indicates the TS header compression modeused by the associated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). TheHC_MODE_TS is signaled according to the below table 25.

TABLE 25 Value Header compression mode 00 HC_MODE_TS 1 01 HC_MODE_TS 210 HC_MODE_TS 3 11 HC_MODE_TS 4

HC_MODE_IP: This 2-bit field indicates the IP header compression modewhen DP_PAYLOAD_TYPE is set to IP (‘01’). The HC_MODE_IP is signaledaccording to the below table 26.

TABLE 26 Value Header compression mode 00 No compression 01 HC_MODE_IP 110~11 reserved

PID: This 13-bit field indicates the PID number for TS headercompression when DP_PAYLOAD_TYPE is set to TS (‘00’) and HC_MODE_TS isset to ‘01’ or ‘10’.

RESERVED: This 8-bit field is reserved for future use.

The following field appears only if FIC_FLAG is equal to ‘1’:

FIC_VERSION: This 8-bit field indicates the version number of the FIC.

FIC_LENGTH_BYTE: This 13-bit field indicates the length, in bytes, ofthe FIC.

RESERVED: This 8-bit field is reserved for future use.

The following field appears only if AUX_FLAG is equal to ‘1’:

NUM_AUX: This 4-bit field indicates the number of auxiliary streams.Zero means no auxiliary streams are used.

AUX_CONFIG_RFU: This 8-bit field is reserved for future use.

AUX_STREAM_TYPE: This 4-bit is reserved for future use for indicatingthe type of the current auxiliary stream.

AUX_PRIVATE_CONFIG: This 28-bit field is reserved for future use forsignaling auxiliary streams.

FIG. 15 illustrates PLS2 data according to another embodiment of thepresent invention.

FIG. 15 illustrates PLS2-DYN data of the PLS2 data. The values of thePLS2-DYN data may change during the duration of one frame-group, whilethe size of fields remains constant.

The details of fields of the PLS2-DYN data are as follows:

FRAME_INDEX: This 5-bit field indicates the frame index of the currentframe within the super-frame. The index of the first frame of thesuper-frame is set to ‘0’.

PLS_CHANGE_COUNTER: This 4-bit field indicates the number ofsuper-frames ahead where the configuration will change. The nextsuper-frame with changes in the configuration is indicated by the valuesignaled within this field. If this field is set to the value ‘0000’, itmeans that no scheduled change is foreseen: e.g., value ‘1’ indicatesthat there is a change in the next super-frame.

FIC_CHANGE_COUNTER: This 4-bit field indicates the number ofsuper-frames ahead where the configuration (i.e., the contents of theFIC) will change. The next super-frame with changes in the configurationis indicated by the value signaled within this field. If this field isset to the value ‘0000’, it means that no scheduled change is foreseen:e.g. value ‘0001’ indicates that there is a change in the nextsuper-frame.

RESERVED: This 16-bit field is reserved for future use.

The following fields appear in the loop over NUM_DP, which describe theparameters associated with the DP carried in the current frame.

DP_ID: This 6-bit field indicates uniquely the DP within a PHY profile.

DP_START: This 15-bit (or 13-bit) field indicates the start position ofthe first of the DPs using the DPU addressing scheme. The DP_START fieldhas differing length according to the PHY profile and FFT size as shownin the below table 27.

TABLE 27 DP_START field size PHY profile 64K 16K Base 13 bits 15 bitsHandheld — 13 bits Advanced 13 bits 15 bits

DP_NUM_BLOCK: This 10-bit field indicates the number of FEC blocks inthe current TI group for the current DP. The value of DP_NUM_BLOCKranges from 0 to 1023

RESERVED: This 8-bit field is reserved for future use.

The following fields indicate the FIC parameters associated with theEAC.

EAC_FLAG: This 1-bit field indicates the existence of the EAC in thecurrent frame. This bit is the same value as the EAC_FLAG in thepreamble.

EAS_WAKE_UP_VERSION_NUM: This 8-bit field indicates the version numberof a wake-up indication.

If the EAC_FLAG field is equal to ‘1’, the following 12 bits areallocated for EAC_LENGTH_BYTE field. If the EAC_FLAG field is equal to‘0’, the following 12 bits are allocated for EAC_COUNTER.

EAC_LENGTH_BYTE: This 12-bit field indicates the length, in byte, of theEAC.

EAC_COUNTER: This 12-bit field indicates the number of the frames beforethe frame where the EAC arrives.

The following field appears only if the AUX_FLAG field is equal to ‘1’:

AUX_PRIVATE_DYN: This 48-bit field is reserved for future use forsignaling auxiliary streams. The meaning of this field depends on thevalue of AUX_STREAM_TYPE in the configurable PLS2-STAT.

CRC_32: A 32-bit error detection code, which is applied to the entirePLS2.

FIG. 16 illustrates a logical structure of a frame according to anembodiment of the present invention.

As above mentioned, the PLS, EAC, FIC, DPs, auxiliary streams and dummycells are mapped into the active carriers of the OFDM symbols in theframe. The PLS1 and PLS2 are first mapped into one or more FSS(s). Afterthat, EAC cells, if any, are mapped immediately following the PLS field,followed next by FIC cells, if any. The DPs are mapped next after thePLS or EAC, FIC, if any. Type 1 DPs follows first, and Type 2 DPs next.The details of a type of the DP will be described later. In some case,DPs may carry some special data for EAS or service signaling data. Theauxiliary stream or streams, if any, follow the DPs, which in turn arefollowed by dummy cells. Mapping them all together in the abovementioned order, i.e. PLS, EAC, FIC, DPs, auxiliary streams and dummydata cells exactly fill the cell capacity in the frame.

FIG. 17 illustrates PLS mapping according to an embodiment of thepresent invention.

PLS cells are mapped to the active carriers of FSS(s). Depending on thenumber of cells occupied by PLS, one or more symbols are designated asFSS(s), and the number of FSS(s) NFSS is signaled by NUM_FSS in PLS1.The FSS is a special symbol for carrying PLS cells. Since robustness andlatency are critical issues in the PLS, the FSS(s) has higher density ofpilots allowing fast synchronization and frequency-only interpolationwithin the FSS.

PLS cells are mapped to active carriers of the NFSS FSS(s) in a top-downmanner as shown in an example in FIG. 17. The PLS1 cells are mappedfirst from the first cell of the first FSS in an increasing order of thecell index. The PLS2 cells follow immediately after the last cell of thePLS1 and mapping continues downward until the last cell index of thefirst FSS. If the total number of required PLS cells exceeds the numberof active carriers of one FSS, mapping proceeds to the next FSS andcontinues in exactly the same manner as the first FSS.

After PLS mapping is completed, DPs are carried next. If EAC, FIC orboth are present in the current frame, they are placed between PLS and“normal” DPs.

FIG. 18 illustrates EAC mapping according to an embodiment of thepresent invention.

EAC is a dedicated channel for carrying EAS messages and links to theDPs for EAS. EAS support is provided but EAC itself may or may not bepresent in every frame. EAC, if any, is mapped immediately after thePLS2 cells. EAC is not preceded by any of the FIC, DPs, auxiliarystreams or dummy cells other than the PLS cells. The procedure ofmapping the EAC cells is exactly the same as that of the PLS.

The EAC cells are mapped from the next cell of the PLS2 in increasingorder of the cell index as shown in the example in FIG. 18. Depending onthe EAS message size, EAC cells may occupy a few symbols, as shown inFIG. 18.

EAC cells follow immediately after the last cell of the PLS2, andmapping continues downward until the last cell index of the last FSS. Ifthe total number of required EAC cells exceeds the number of remainingactive carriers of the last FSS mapping proceeds to the next symbol andcontinues in exactly the same manner as FSS(s). The next symbol formapping in this case is the normal data symbol, which has more activecarriers than a FSS.

After EAC mapping is completed, the FIC is carried next, if any exists.If FIC is not transmitted (as signaled in the PLS2 field), DPs followimmediately after the last cell of the EAC.

FIG. 19 illustrates FIC mapping according to an embodiment of thepresent invention.

shows an example mapping of FIC cell without EAC and (b) shows anexample mapping of FIC cell with EAC.

FIC is a dedicated channel for carrying cross-layer information toenable fast service acquisition and channel scanning. This informationprimarily includes channel binding information between DPs and theservices of each broadcaster. For fast scan, a receiver can decode FICand obtain information such as broadcaster ID, number of services, andBASE_DP_ID. For fast service acquisition, in addition to FIC, base DPcan be decoded using BASE_DP_ID. Other than the content it carries, abase DP is encoded and mapped to a frame in exactly the same way as anormal DP. Therefore, no additional description is required for a baseDP. The FIC data is generated and consumed in the Management Layer. Thecontent of FIC data is as described in the Management Layerspecification.

The FIC data is optional and the use of FIC is signaled by the FIC_FLAGparameter in the static part of the PLS2. If FIC is used, FIC_FLAG isset to ‘1’ and the signaling field for FIC is defined in the static partof PLS2. Signaled in this field are FIC_VERSION, and FIC_LENGTH_BYTE.FIC uses the same modulation, coding and time interleaving parameters asPLS2. FIC shares the same signaling parameters such as PLS2_MOD andPLS2_FEC. FIC data, if any, is mapped immediately after PLS2 or EAC ifany. FIC is not preceded by any normal DPs, auxiliary streams or dummycells. The method of mapping FIC cells is exactly the same as that ofEAC which is again the same as PLS.

Without EAC after PLS, FIC cells are mapped from the next cell of thePLS2 in an increasing order of the cell index as shown in an example in(a). Depending on the FIC data size, FIC cells may be mapped over a fewsymbols, as shown in (b).

FIC cells follow immediately after the last cell of the PLS2, andmapping continues downward until the last cell index of the last FSS. Ifthe total number of required FIC cells exceeds the number of remainingactive carriers of the last FSS, mapping proceeds to the next symbol andcontinues in exactly the same manner as FSS(s). The next symbol formapping in this case is the normal data symbol which has more activecarriers than a FSS.

If EAS messages are transmitted in the current frame, EAC precedes FIC,and FIC cells are mapped from the next cell of the EAC in an increasingorder of the cell index as shown in (b).

After FIC mapping is completed, one or more DPs are mapped, followed byauxiliary streams, if any, and dummy cells.

FIG. 20 illustrates a type of DP according to an embodiment of thepresent invention.

shows type 1 DP and (b) shows type 2 DP.

After the preceding channels, i.e., PLS, EAC and FIC, are mapped, cellsof the DPs are mapped. A DP is categorized into one of two typesaccording to mapping method:

Type 1 DP: DP is mapped by TDM

Type 2 DP: DP is mapped by FDM

The type of DP is indicated by DP_TYPE field in the static part of PLS2.FIG. 20 illustrates the mapping orders of Type 1 DPs and Type 2 DPs.Type 1 DPs are first mapped in the increasing order of cell index, andthen after reaching the last cell index, the symbol index is increasedby one. Within the next symbol, the DP continues to be mapped in theincreasing order of cell index starting from p=0. With a number of DPsmapped together in one frame, each of the Type 1 DPs are grouped intime, similar to TDM multiplexing of DPs.

Type 2 DPs are first mapped in the increasing order of symbol index, andthen after reaching the last OFDM symbol of the frame, the cell indexincreases by one and the symbol index rolls back to the first availablesymbol and then increases from that symbol index. After mapping a numberof DPs together in one frame, each of the Type 2 DPs are grouped infrequency together, similar to FDM multiplexing of DPs.

Type 1 DPs and Type 2 DPs can coexist in a frame if needed with onerestriction; Type 1 DPs always precede Type 2 DPs. The total number ofOFDM cells carrying Type 1 and Type 2 DPs cannot exceed the total numberof OFDM cells available for transmission of DPs:

D _(DP1) +D _(DP2) ≦D _(DP)  [Math figure 2]

where DDP1 is the number of OFDM cells occupied by Type 1 DPs, DDP2 isthe number of cells occupied by Type 2 DPs. Since PLS, EAC, FIC are allmapped in the same way as Type 1 DP, they all follow “Type 1 mappingrule”. Hence, overall, Type 1 mapping always precedes Type 2 mapping.

FIG. 21 illustrates DP mapping according to an embodiment of the presentinvention.

shows an addressing of OFDM cells for mapping type 1 DPs and (b) showsan addressing of OFDM cells for mapping for type 2 DPs.

Addressing of OFDM cells for mapping Type 1 DPs (0, . . . , DDP1-1) isdefined for the active data cells of Type 1 DPs. The addressing schemedefines the order in which the cells from the TIs for each of the Type 1DPs are allocated to the active data cells. It is also used to signalthe locations of the DPs in the dynamic part of the PLS2.

Without EAC and FIC, address 0 refers to the cell immediately followingthe last cell carrying PLS in the last FSS. If EAC is transmitted andFIC is not in the corresponding frame, address 0 refers to the cellimmediately following the last cell carrying EAC. If FIC is transmittedin the corresponding frame, address 0 refers to the cell immediatelyfollowing the last cell carrying FIC. Address 0 for Type 1 DPs can becalculated considering two different cases as shown in (a). In theexample in (a), PLS, EAC and FIC are assumed to be all transmitted.Extension to the cases where either or both of EAC and FIC are omittedis straightforward. If there are remaining cells in the FSS aftermapping all the cells up to FIC as shown on the left side of (a).

Addressing of OFDM cells for mapping Type 2 DPs (0, . . . , DDP2-1) isdefined for the active data cells of Type 2 DPs. The addressing schemedefines the order in which the cells from the TIs for each of the Type 2DPs are allocated to the active data cells. It is also used to signalthe locations of the DPs in the dynamic part of the PLS2.

Three slightly different cases are possible as shown in (b). For thefirst case shown on the left side of (b), cells in the last FSS areavailable for Type 2 DP mapping. For the second case shown in themiddle, FIC occupies cells of a normal symbol, but the number of FICcells on that symbol is not larger than CFSS. The third case, shown onthe right side in (b), is the same as the second case except that thenumber of FIC cells mapped on that symbol exceeds CFSS.

The extension to the case where Type 1 DP(s) precede Type 2 DP(s) isstraightforward since PLS, EAC and FIC follow the same “Type 1 mappingrule” as the Type 1 DP(s).

A data pipe unit (DPU) is a basic unit for allocating data cells to a DPin a frame.

A DPU is defined as a signaling unit for locating DPs in a frame. A CellMapper 7010 may map the cells produced by the TIs for each of the DPs. ATime interleaver 5050 outputs a series of TI-blocks and each TI-blockcomprises a variable number of XFECBLOCKs which is in turn composed of aset of cells. The number of cells in an XFECBLOCK, Ncells, is dependenton the FECBLOCK size, Nldpc, and the number of transmitted bits perconstellation symbol. A DPU is defined as the greatest common divisor ofall possible values of the number of cells in a XFECBLOCK, Ncells,supported in a given PHY profile. The length of a DPU in cells isdefined as LDPU. Since each PHY profile supports different combinationsof FECBLOCK size and a different number of bits per constellationsymbol, LDPU is defined on a PHY profile basis.

FIG. 22 illustrates an FEC structure according to an embodiment of thepresent invention.

FIG. 22 illustrates an FEC structure according to an embodiment of thepresent invention before bit interleaving. As above mentioned, Data FECencoder may perform the FEC encoding on the input BBF to generateFECBLOCK procedure using outer coding (BCH), and inner coding (LDPC).The illustrated FEC structure corresponds to the FECBLOCK. Also, theFECBLOCK and the FEC structure have same value corresponding to a lengthof LDPC codeword.

The BCH encoding is applied to each BBF (Kbch bits), and then LDPCencoding is applied to BCH-encoded BBF (Kldpc bits=Nbch bits) asillustrated in FIG. 22.

The value of Nldpc is either 64800 bits (long FECBLOCK) or 16200 bits(short FECBLOCK).

The below table 28 and table 29 show FEC encoding parameters for a longFECBLOCK and a short FECBLOCK, respectively.

TABLE 28 BCH error LDPC correction Nbch − Rate Nldpc Kldpc Kbchcapability Kbch 5/15 64800 21600 21408 12 192 6/15 25920 25728 7/1530240 30048 8/15 34560 34368 9/15 38880 38688 10/15  43200 43008 11/15 47520 47328 12/15  51840 51648 13/15  56160 55968

TABLE 29 BCH error LDPC correction Nbch − Rate Nldpc Kldpc Kbchcapability Kbch 5/15 16200 5400 5232 12 168 6/15 6480 6312 7/15 75607392 8/15 8640 8472 9/15 9720 9552 10/15  10800 10632 11/15  11880 1171212/15  12960 12792 13/15  14040 13872

The details of operations of the BCH encoding and LDPC encoding are asfollows:

A 12-error correcting BCH code is used for outer encoding of the BBF.The BCH generator polynomial for short FECBLOCK and long FECBLOCK areobtained by multiplying together all polynomials.

LDPC code is used to encode the output of the outer BCH encoding. Togenerate a completed Bldpc (FECBLOCK), Pldpc (parity bits) is encodedsystematically from each Ildpc (BCH-encoded BBF), and appended to Ildpc.The completed Bldpc (FECBLOCK) are expressed as follow Math figure.

B _(ldpc) =[I _(ldpc) P _(ldpc) ]=[i ₀ ,i ₁ , . . . ,i _(K) _(ldpc) ⁻¹,p ₀ ,p ₁ , . . . ,p _(N) _(ldpc) _(−K) _(ldpc) ⁻¹]  [Math figure 3]

The parameters for long FECBLOCK and short FECBLOCK are given in theabove table 28 and 29, respectively.

The detailed procedure to calculate Nldpc−Kldpc parity bits for longFECBLOCK, is as follows:

1) Initialize the parity bits,

p ₀ =p ₁ =p ₂ = . . . =p _(N) _(ldpc) _(−K) _(ldpc) ⁻¹=0  [Math figure4]

2) Accumulate the first information bit—i0, at parity bit addressesspecified in the first row of an addresses of parity check matrix. Thedetails of addresses of parity check matrix will be described later. Forexample, for rate 13/15:

p ₉₈₃ =p ₉₈₃ ⊕i ₀ p ₂₈₁₅ =p ₂₈₁₅ ⊕i ₀

p ₄₈₃₇ =p ₄₈₃₇ ⊕i ₀ p ₄₉₈₉ =p ₄₉₈₉ ⊕i ₀

p ₆₁₃₈ =p ₆₁₃₈ ⊕i ₀ p ₆₄₅₈ =p ₆₄₅₈ ⊕i ₀

p ₆₉₂₁ =p ₆₉₂₁ ⊕i ₀ p ₆₉₇₄ =p ₆₉₇₄ ⊕i ₀

p ₇₅₇₂ =p ₇₅₇₂ ⊕i ₀ p ₈₂₆₀ =p ₈₂₆₀ ⊕i ₀

p ₈₄₉₆ =p ₈₄₉₆ ⊕i ₀  [Math figure 5]

3) For the next 359 information bits, is, s=1, 2, . . . , 359 accumulateis at parity bit addresses using following Math figure.

{x+(s mod 360)×Q _(ldpc)} mod(N _(ldpc) −K _(ldpc))  [Math figure 6]

where x denotes the address of the parity bit accumulator correspondingto the first bit i0, and Qldpc is a code rate dependent constantspecified in the addresses of parity check matrix. Continuing with theexample, Qldpc=24 for rate 13/15, so for information bit i1, thefollowing operations are performed:

p ₁₀₀₇ =p ₁₀₀₇ ⊕i ₁ p ₂₈₃₉ =p ₂₈₃₉ ⊕i ₁

p ₄₈₆₁ =p ₄₈₆₁ ⊕i ₁ p ₅₀₁₃ =p ₅₀₁₃ ⊕i ₁

p ₆₁₆₂ =p ₆₁₆₂ ⊕i ₁ p ₆₄₈₂ =p ₆₄₈₂ ⊕i ₁

p ₆₉₄₅ =p ₆₉₄₅ ⊕i ₁ p ₆₉₉₈ =p ₆₉₉₈ ⊕i ₁

p ₇₅₉₆ =p ₇₅₉₆ ⊕i ₁ p ₈₂₈₄ =p ₈₂₈₄ ⊕i ₁

p ₈₅₂₀ =p ₈₅₂₀ ⊕i ₁  [Math figure 7]

4) For the 361st information bit i360, the addresses of the parity bitaccumulators are given in the second row of the addresses of paritycheck matrix. In a similar manner the addresses of the parity bitaccumulators for the following 359 information bits is, s=361, 362, . .. , 719 are obtained using the Math figure 6, where x denotes theaddress of the parity bit accumulator corresponding to the informationbit i360, i.e., the entries in the second row of the addresses of paritycheck matrix.

5) In a similar manner, for every group of 360 new information bits, anew row from addresses of parity check matrixes used to find theaddresses of the parity bit accumulators.

After all of the information bits are exhausted, the final parity bitsare obtained as follows:

6) Sequentially perform the following operations starting with i=1

p _(i) =p _(i) ⊕p _(i-1) ,i=1,2, . . . ,N _(ldpc) −K _(ldpc)−1  [Mathfigure 8]

where final content of pi, i=0, 1, . . . Nldpc−Kldpc−1 is equal to theparity bit pi.

TABLE 30 Code Rate Qldpc 5/15 120 6/15 108 7/15 96 8/15 84 9/15 7210/15  60 11/15  48 12/15  36 13/15  24

This LDPC encoding procedure for a short FECBLOCK is in accordance witht LDPC encoding procedure for the long FECBLOCK, except replacing thetable 30 with table 31, and replacing the addresses of parity checkmatrix for the long FECBLOCK with the addresses of parity check matrixfor the short FECBLOCK.

TABLE 31 Code Rate Qldpc 5/15 30 6/15 27 7/15 24 8/15 21 9/15 18 10/15 15 11/15  12 12/15  9 13/15  6

FIG. 23 illustrates a bit interleaving according to an embodiment of thepresent invention.

The outputs of the LDPC encoder are bit-interleaved, which consists ofparity interleaving followed by Quasi-Cyclic Block (QCB) interleavingand inner-group interleaving.

shows Quasi-Cyclic Block (QCB) interleaving and (b) shows inner-groupinterleaving.

The FECBLOCK may be parity interleaved. At the output of the parityinterleaving, the LDPC codeword consists of 180 adjacent QC blocks in along FECBLOCK and 45 adjacent QC blocks in a short FECBLOCK. Each QCblock in either a long or short FECBLOCK consists of 360 bits. Theparity interleaved LDPC codeword is interleaved by QCB interleaving. Theunit of QCB interleaving is a QC block. The QC blocks at the output ofparity interleaving are permutated by QCB interleaving as illustrated inFIG. 23, where Ncells=64800/η mod or 16200/η mod according to theFECBLOCK length. The QCB interleaving pattern is unique to eachcombination of modulation type and LDPC code rate.

After QCB interleaving, inner-group interleaving is performed accordingto modulation type and order (η mod) which is defined in the below table32. The number of QC blocks for one inner-group, NQCB_IG, is alsodefined.

TABLE 32 Modulation type ηmod NQCB_IG QAM-16 4 2 NUC-16 4 4 NUQ-64 6 3NUC-64 6 6 NUQ-256 8 4 NUC-256 8 8 NUQ-1024 10 5 NUC-1024 10 10

The inner-group interleaving process is performed with NQCB_IG QC blocksof the QCB interleaving output. Inner-group interleaving has a processof writing and reading the bits of the inner-group using 360 columns andNQCB_IG rows. In the write operation, the bits from the QCB interleavingoutput are written row-wise. The read operation is performed column-wiseto read out m bits from each row, where m is equal to 1 for NUC and 2for NUQ.

FIG. 24 illustrates a cell-word demultiplexing according to anembodiment of the present invention.

shows a cell-word demultiplexing for 8 and 12 bpcu MIMO and (b) shows acell-word demultiplexing for 10 bpcu MIMO.

Each cell word (c0,l, c1,l, . . . , cη mod−1,l) of the bit interleavingoutput is demultiplexed into (d1,0,m, d1,1,m . . . , d1,η mod−1,m) and(d2,0,m, d2,1,m . . . , d2,η mod−1,m) as shown in (a), which describesthe cell-word demultiplexing process for one XFECBLOCK.

For the 10 bpcu MIMO case using different types of NUQ for MIMOencoding, the Bit Interleaver for NUQ-1024 is re-used. Each cell word(c0,1, c1,1, . . . , c9,1) of the Bit Interleaver output isdemultiplexed into (d1,0,m, d1,1,m . . . , d1,3,m) and (d2,0,m, d2,1,m .. . , d2,5,m), as shown in (b).

FIG. 25 illustrates a time interleaving according to an embodiment ofthe present invention.

to (c) show examples of TI mode.

The time interleaver operates at the DP level. The parameters of timeinterleaving (TI) may be set differently for each DP.

The following parameters, which appear in part of the PLS2-STAT data,configure the TI:

DP_TI_TYPE (allowed values: 0 or 1): Represents the TI mode; ‘0’indicates the mode with multiple TI blocks (more than one TI block) perTI group. In this case, one TI group is directly mapped to one frame (nointer-frame interleaving). ‘1’ indicates the mode with only one TI blockper TI group. In this case, the TI block may be spread over more thanone frame (inter-frame interleaving).

DP_TI_LENGTH: If DP_TI_TYPE=‘0’, this parameter is the number of TIblocks NTI per TI group. For DP_TI_TYPE=‘1’, this parameter is thenumber of frames PI spread from one TI group.

DP_NUM_BLOCK_MAX (allowed values: 0 to 1023): Represents the maximumnumber of XFECBLOCKs per TI group.

DP_FRAME_INTERVAL (allowed values: 1, 2, 4, 8): Represents the number ofthe frames IJUMP between two successive frames carrying the same DP of agiven PHY profile.

DP_TI_BYPASS (allowed values: 0 or 1): If time interleaving is not usedfor a DP, this parameter is set to ‘1’. It is set to ‘0’ if timeinterleaving is used.

Additionally, the parameter DP_NUM_BLOCK from the PLS2-DYN data is usedto represent the number of XFECBLOCKs carried by one TI group of the DP.

When time interleaving is not used for a DP, the following TI group,time interleaving operation, and TI mode are not considered. However,the Delay Compensation block for the dynamic configuration informationfrom the scheduler will still be required. In each DP, the XFECBLOCKsreceived from the SSD/MIMO encoding are grouped into TI groups. That is,each TI group is a set of an integer number of XFECBLOCKs and willcontain a dynamically variable number of XFECBLOCKs. The number ofXFECBLOCKs in the TI group of index n is denoted by NxBLOCK_Group(n) andis signaled as DP_NUM_BLOCK in the PLS2-DYN data. Note thatNxBLOCK_Group(n) may vary from the minimum value of 0 to the maximumvalue NxBLOCK_Group_MAX (corresponding to DP_NUM_BLOCK_MAX) of which thelargest value is 1023.

Each TI group is either mapped directly onto one frame or spread over PIframes. Each TI group is also divided into more than one TI blocks(NTI),where each TI block corresponds to one usage of time interleaver memory.The TI blocks within the TI group may contain slightly different numbersof XFECBLOCKs. If the TI group is divided into multiple TI blocks, it isdirectly mapped to only one frame. There are three options for timeinterleaving (except the extra option of skipping the time interleaving)as shown in the below table 33.

TABLE 33 Mode Description Option-1 Each TI group contains one TI blockand is mapped directly to one frame as shown in (a). This option issignaled in the PLS2-STAT by DP_TI_TYPE = ‘0’ and DP_TI_LENGTH = ‘1’(NTI = 1). Option-2 Each TI group contains one TI block and is mapped tomore than one frame. (b) shows an example, where one TI group is mappedto two frames, i.e., DP_TI_LENGTH = ‘2’ (PI = 2) and DP_FRAME_INTERVAL(IJUMP = 2). This provides greater time diversity for low data-rateservices. This option is signaled in the PLS2-STAT by DP_TI_TYPE = ‘1’.Option-3 Each TI group is divided into multiple TI blocks and is mappeddirectly to one frame as shown in (c). Each TI block may use full TImemory, so as to provide the maximum bit-rate for a DP. This option issignaled in the PLS2-STAT signaling by DP_TI_TYPE = ‘0’ and DP_TI_LENGTH= NTI, while PI = 1.

In each DP, the TI memory stores the input XFECBLOCKs (output XFECBLOCKsfrom the SSD/MIMO encoding block). Assume that input XFECBLOCKs aredefined as

(d _(n,s,0,) ,d _(n,s,0,1) , . . . ,d _(n,s,0,N) _(cells) ⁻¹ ,d_(n,s,1,0) , . . . ,d _(n,s,1,N) _(cells) ⁻¹ , . . . ,d _(n,s,N)_(xBLOCKTI) _((n,s)−1,0) , . . . ,d _(n,s,N) _(xBLOCKTI) _((n,s)−1,N)_(cells) ⁻¹),

where d_(n,s,r,q) is the qth cell of the rth XFECBLOCK in the sth TIblock of the nth TI group and represents the outputs of SSD and MIMOencodings as follows

$d_{n,s,r,q} = \left\{ {\begin{matrix}{f_{n,s,r,q},} & {{the}\mspace{14mu} {output}\mspace{14mu} {of}\mspace{14mu} S\; S\; D\mspace{14mu} \ldots \mspace{14mu} {encoding}} \\{g_{n,s,r,q},} & {{the}\mspace{14mu} {output}\mspace{14mu} {of}\mspace{14mu} M\; I\; M\; O\mspace{14mu} {encoding}}\end{matrix}.} \right.$

In addition, assume that output XFECBLOCKs from the time interleaver5050 are defined as

(h _(n,s,0) ,h _(n,s,1) , . . . ,h _(n,s,i) , . . . ,h _(n,s,N)_(xBLOCKTI) _((n,s)×N) _(cells) ⁻¹),

where h_(n,s,i) is the ith output cell (for i=0, . . . , N_(xBLOCK) _(_)_(TI)(n,s)×N_(cells)−1) in the sth TI block of the nth TI group.

Typically, the time interleaver will also act as a buffer for DP dataprior to the process of frame building. This is achieved by means of twomemory banks for each DP. The first TI-block is written to the firstbank. The second TI-block is written to the second bank while the firstbank is being read from and so on.

The TI is a twisted row-column block interleaver. For the sth TI blockof the nth TI group, the number of rows N_(r) of a TI memory is equal tothe number of cells N_(cells), i.e., N_(r)=N_(cells) while the number ofcolumns N_(c) is equal to the number N_(xBLOCK) _(_) _(TI)(n,s).

FIG. 26 illustrates a basic operation of a twisted row-column blockinterleaver according to an exemplary embodiment of the presentinvention.

FIG. 26A illustrates a writing operation in a time interleaver and FIG.26B illustrates a reading operation in the time interleaver. Asillustrated in FIG. 26A, a first XFECBLOCK is written in a first columnof a time interleaving memory in a column direction and a secondXFECBLOCK is written in a next column, and such an operation iscontinued. In addition, in an interleaving array, a cell is read in adiagonal direction. As illustrated in FIG. 26B, while the diagonalreading is in progress from a first row (to a right side along the rowstarting from a leftmost column) to a last row, N_(y) cells are read. Indetail, when it is assumed that z_(n,s,1)(i=0, . . . , N_(r)N_(c)) is atime interleaving memory cell position to be sequentially read, thereading operation in the interleaving array is executed by calculating arow index R_(n,s,1), a column index C_(n,s,1), and associated twistparameter T_(n,s,1) as shown in an equation given below.

$\begin{matrix}{{{GENERATE}\mspace{14mu} \left( {R_{n,s,i},C_{n,s,i}} \right)} = \left\{ {{R_{n,s,i} = {{mod}\left( {,N_{r}} \right)}},{T_{n,s,i} = {{mod}\left( {{S_{shift} \times R_{n,s,i}},N_{c}} \right)}},{C_{n,s,i} = {{mod}\left( {{T_{n,s,i} + \left\lfloor \frac{}{N_{r}} \right\rfloor},N_{c}} \right)}}} \right\}} & \left\lbrack {{Equation}\mspace{14mu} 9} \right\rbrack\end{matrix}$

Where, S_(shift) is a common shift value for a diagonal reading processregardless of N_(xBLOCK TI)(n,s) and the shift value is decided byN_(xBLOCK TI MAX) given in PLS2-STAT as shown in an equation givenbelow.

                                     [Equation  10] $\begin{matrix}{\mspace{79mu} {{for}\left\{ {\begin{matrix}{{N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime} = {N_{{xBLOCK\_ TI}{\_ MAX}} + 1}},} & {{{if}\mspace{14mu} N_{{xBLOCK\_ TI}{\_ MAX}}{mod}\; 2} = 0} \\{{N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime} = N_{{xBLOCK\_ TI}{\_ MAX}}},} & {{{if}\mspace{14mu} N_{{xBLOCK\_ TI}{\_ MAX}}{mod}\; 2} = 1}\end{matrix},\mspace{79mu} {S_{shift} = \frac{N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime} - 1}{2}}} \right.}} & \;\end{matrix}$

Consequently, the cell position to be read is calculated by a coordinatez_(n,s,i)=N_(r)C_(n,s,1)+R_(n,s,1).

FIG. 27 illustrates an operation of a twisted row-column blockinterleaver according to another exemplary embodiment of the presentinvention.

In more detail, FIG. 27 illustrates an interleaving array in the timeinterleaving memory for respective time interleaving groups including avirtual XFECBLOCK when N_(xBLOCK) _(—TI) (0,0)=3, N_(xBLOCK TI)(1,0)=6,and N_(xBLOCK TI)(2,0)−5.

A variable N_(xBLOCK TI)(n,s)=N, will be equal to or smaller thanN′_(xBLOCK) _(_) _(TI) _(_) _(MAX). Accordingly, in order for a receiverto achieve single memory interleaving regardless of N_(xBLOCK) _(_)_(TI)(n,s), the size of the interleaving array for the twistedrow-column block interleaver is set to a size ofN₁×N_(c)=N_(cells)×N′_(xBLOCK) _(_) _(TI) _(_) _(MAX) by inserting thevirtual XFECBLOCK into the time interleaving memory and a readingprocess is achieved as shown in an equation given below.

[Equation 11] p = 0; for i = 0;i < N_(cells)N_(xBLOCK) _(—) _(TI) _(—)_(MAX)′;i = i + 1 {GENERATE (R_(n,s,i),C_(n,s,i)); V_(i) =N_(r)C_(n,s,j) + R_(n,s,j)  if V_(i) < N_(cells)N_(xBLOCK TI)(n,s)  {  Z_(n,s,p) = V_(i); p = p + 1;   } }

The number of the time interleaving groups is set to 3. An option of thetime interleaver is signaled in the PLS2-STAT by DP_TI_TYPE=‘0’,DP_FRAME_INTERVAL=‘1’, and DP_TI_LENGTH=‘1’, that is, NTI=1, IJUMP=1,and PI=1. The number of respective XFECBLOCKs per time interleavinggroup, of which Ncells=30 is signaled in PLS2-DYN data byNxBLOCK_TI(0,0)=3, NxBLOCK_TI(1,0)=6, and NxBLOCK_TI(2,0)=5 of therespective XFECBLOCKs. The maximum number of XFECBLOCKs is signaled inthe PLS2-STAT data by NxBLOCK_Group_MAX and this is continued to└N_(xBLOCK) _(_) _(Group) _(_) _(MAX)/N_(TI)┘=N_(xBLOCK) _(_) _(TI) _(_)_(MAX)=6.

FIG. 28 illustrates a diagonal reading pattern of the twisted row-columnblock interleaver according to the exemplary embodiment of the presentinvention.

In more detail, FIG. 28 illustrates a diagonal reading pattern fromrespective interleaving arrays having parameters N′_(xBLOCK TI MAX)=7and Sshift=(7−1)/2=3. In this case, during a reading process expressedby a pseudo code given above, when V_(i)≧N_(cells)N_(xBLOCK) _(_)_(TI)(n,s), a value of Vi is omitted and a next calculation value of Viis used.

FIG. 29 illustrates XFECBLOCK interleaved from each interleaving arrayaccording to an exemplary embodiment of the present invention.

FIG. 29 illustrates XFECBLOCK interleaved from each interleaving arrayhaving parameters N′_(xBLOCK) _(_) _(TI) _(_) _(MAX)=7 and Sshift=3according to an exemplary embodiment of the present invention.

FIG. 30 illustrates a synchronization and demodulation module accordingto an embodiment of the present invention.

The synchronization and demodulation module illustrated in FIG. 30corresponds to the embodiment of the synchronization and demodulationmodule described in FIG. 9. Further, the synchronization anddemodulation module illustrated in FIG. 30 may perform an inverseoperation of the waveform generation module described in FIG. 9.

As illustrated in FIG. 30, the synchronization and demodulation moduleaccording to the embodiment of the present invention as an embodiment ofa synchronization and demodulation module of a receiving apparatus usingm Rx antennas may include m processing blocks for demodulating andoutputting a signal input as long as m paths. All m processing blocksmay perform the same processing procedure. Hereinafter, an operation ofa first processing block 30000 among m processing blocks will beprimarily described.

The first processing block 30000 may include a tuner 30100, an ADC block30200, a preamble detector 30300, a guard sequence detector 30400, awaveform transform block 30500, a time/frequency synchronization block30600, a reference signal detector 30700, a channel equalizer 30800, andan inverse waveform transform block 30900.

The tuner 30100 selects a desired frequency band and compensates amagnitude of a received signal to output the signal to the ADC block30200.

The ADC block 30200 may transform the signal output from the tuner 30100to a digital signal.

The preamble detector 30300 may detect a preamble (alternatively, apreamble signal or a preamble symbol) in order to verify whether thedigital signal is a signal of a system corresponding to the receivingapparatus. In this case, the preamble detector 30300 may decode basictransmission parameters received through the preamble.

The guard sequence detector 30400 may detect a guard sequence in thedigital signal. The time frequency synchronization block 30600 mayperform time/frequency synchronization by using the detected guardsequence and the channel equalizer 30800 may estimate a channel througha sequence received/restored by using the detected guard sequence.

When inverse waveform transform is performed at a transmitting side, thewaveform transform block 30500 may perform an inverse transformprocedure to the inverse waveform transform. When a broadcasttransmitting/receiving system according to the embodiment of the presentinvention a multi-carrier system, the waveform transform block 30500 mayperform an FFT transform procedure. Further, in the case where thebroadcast transmitting/receiving system according to the embodiment ofthe present invention is a single carrier system, when received signalsin a time domain are used to be processed in a frequency domain or allof the received signals are processed in the time domain, the waveformtransform block 30500 may not be used.

The time/frequency synchronization block 30600 may receive output dataof the preamble detector 30300, the guard sequence detector 30400, andthe reference signal detector 30700 and perform time synchronization andcarrier frequency synchronization including guard sequence detection andblock window positioning for a detected signal. In this case, thetime/frequency synchronization block 30600 may feed back and use anoutput signal of the waveform transform block 30500 for frequencysynchronization.

The reference signal detector 30700 may detect a received referencesignal. Therefore, the receiving apparatus according to the embodimentof the present invention may perform synchronization or channelestimation.

The channel equalizer 30800 may estimate a transmission channel up toeach receiving apparatus from each transmitting antenna from the guardsequence or the reference signal and perform channel equalization foreach received data by using the estimated channel.

When the waveform transform block 30500 performs waveform transform inorder to efficiently perform the synchronization and channelestimation/equalization, the inverse waveform transform block 30900 mayserve to restore each received data to an original received data domainagain. In the case where the broadcast transmitting/receiving systemaccording to the embodiment of the present invention is the singlecarrier system, the waveform transform block 30500 may perform FFT inorder to perform the synchronization/channel estimation/equalization inthe frequency domain and the inverse waveform transform block 30900performs IFFT for a signal of which channel equalization is completed torestore a transmitted data symbol. When the broadcasttransmitting/receiving system according to the embodiment of the presentinvention is a multi-carrier system, the inverse waveform transformblock 30900 may not be used.

Further, the aforementioned blocks may be omitted according to anintention of a designer or substituted by other blocks having a similaror the same function.

FIG. 31 illustrates a frame parsing module according to an embodiment ofthe present invention.

The frame parsing module illustrated in FIG. 31 correspond to theembodiment of the frame parsing module described in FIG. 9.

As illustrated in FIG. 31, the frame parsing module according to theembodiment of the present invention may include at least one or moreblock deinterleavers 31000 and at least one or more cell demapper 31100.

The block deinterleaver 31000 may perform deinterleaving for data pereach signal block with respect to data input into respective data pathsof m receiving antennas and processed in the synchronization anddemodulation module. In this case, as described in FIG. 8, whenpair-wise interleaving is performed at the transmitting side, the blockdeinterleaver 31000 may process two consecutive data for each input pathas one pair. Therefore, the block deinterleaver 31000 may output twoconsecutive output data even when deinterleaving the data. Further, theblock deinterleaver 31000 performs an inverse procedure of theinterleaving procedure performed at the transmitting side to output thedata according to an original data sequence.

The cell demapper 31100 may extract cells corresponding to common datafrom a received signal frame, cells corresponding to a data pipe, andcells corresponding to PLS data. In case of need, the cell demapper31100 merges data distributed and transmitted to a plurality of parts tooutput the merged data as one stream. Further, as described in FIG. 7,when two consecutive cell input data are processed as one pair to bemapped, the cell demapper 31100 may perform the pair-wise cell demappingof processing two consecutive input cells as one unit as an inverseprocedure corresponding thereto.

Further, the cell demapper 31100 may extract and output all PLSsignaling data received through a current frame as PLS-pre and PLS-postdata, respectively.

The aforementioned blocks may be omitted according to an intention of adesigner or substituted by other blocks having a similar or the samefunction.

FIG. 32 illustrates a demapping and decoding module according to anembodiment of the present invention.

The demapping and decoding module illustrated in FIG. 32 corresponds tothe embodiment of the demapping and decoding module described in FIG. 9.

As described above, the coding and modulation module of the transmittingapparatus according to the embodiment of the present invention mayindependently apply and process SISO, MISO, and MIMO schemes to inputdata pipes for respective paths. Therefore, the demapping and decodingmodule illustrated in FIG. 32 may also include blocks for SISO, MISO,and MIMO-processing data output from a frame parser to correspond to thetransmitting apparatus, respectively.

As illustrated in FIG. 32, the demapping and decoding module accordingto the embodiment of the present invention may include a first block32000 for the SISO scheme, a second block 32100 for the MISO scheme, anda third block 32200 for the MIMO scheme, and a fourth block 32300processing PLS pre/post information. The demapping and decoding moduleillustrated in FIG. 32 is just an embodiment and the demapping anddecoding module may include only the first block 32000 and the fourthblock 32300, only the second block 32100 and the fourth block 32300, andonly the third block 32200 and the fourth block 32300 according to theintension of the designer. That is, the demapping and decoding modulemay include blocks for processing the respective data pipes similarly ordifferently according to the intention of the designer.

Hereinafter, each block will be described.

The first block 32000 as a block for SISO-processing the input data pipemay include a time de-interleaver block 32010, a cell de-interleaverblock 32020, a constellation demapper block 32030, a cell to bit muxblock 32040, a bit de-interleaver block 32050, and an FEC decoder block32060.

The time de-interleaver block 32010 may perform an inverse procedure ofa time interleaver block. That is, the time de-interleaver block 32010may deinterleave an input symbol interleaved in the time domain to anoriginal position.

The cell de-interleaver block 32020 may perform an inverse procedure ofa cell interleaver block. That is, the cell de-interleaver block 32020may deinterleave positions of cells spread in one FEC block to originalpositions.

The constellation demapper block 32030 may perform an inverse procedureof a constellation mapper block. That is, the constellation demapperblock 32030 may demap an input signal of a symbol domain to data of abit domain. Further, the constellation demapper block 32030 may outputbit data decided by performing a hard decision and output alog-likelihood ratio (LLR) of each bit corresponding to a soft decisionvalue or a probabilistic value. When the transmitting side applies arotated constellation in order to acquire an additional diversity gain,the constellation demapper block 32030 may perform 2-dimensional LLRdemapping corresponding to the rotated constellation. In this case, theconstellation demapper 32030 may perform a calculation so that thetransmitting apparatus compensates a delay value performed with respectto an I or Q component at the time of calculating the LLR.

The cell to bit mux block 32040 may perform an inverse procedure of abit to cell demux block. That is, the cell to bit mux block 32040 mayrestore bit data mapped in a bit to cell demux block to an original bitstream form.

The bit de-interleaver block 32050 may perform an inverse procedure of abit interleaver block. That is, the bit de-interleaver block 32050 maydeinterleave the bit stream output in the cell to bit mux block 32040according to an original sequence.

The FEC decoder block 32060 may perform an inverse procedure of an FECencoder block. That is, the FEC decoder block 32060 may correct an errorwhich occurs on a transmission channel by performing LDPC decoding andBCH decoding.

The second block 32100 as a block for MISO-processing the input datapipe may include the time de-interleaver block, the cell de-interleaverblock, the constellation demapper block, the cell to bit mux block, thebit de-interleaver block, and the FEC decoder block similarly to thefirst block 32000 as illustrated in FIG. 32, but the second block 32100is different from the first block 32000 in that the second block 32100further includes an MISO decoding block 32110. Since the second block32100 performs a procedure of the same role from the time deinterleaverup to the output similarly to the first block 32000, a description ofthe same blocks will be omitted.

The MISO decoding block 32110 may perform an inverse procedure of theMISO processing block. When the broadcast transmitting/receiving systemaccording to the embodiment of the present invention is a system usingSTBC, the MISO decoding block 32110 may perform Alamouti decoding.

The third block 32200 as a block for MIMO-processing the input data pipemay include the time de-interleaver block, the cell de-interleaverblock, the constellation demapper block, the cell to bit mux block, thebit de-interleaver block, and the FEC decoder block similarly to thesecond block 32100 as illustrated in FIG. 32, but the third block 32200is different from the second block 32100 in that the third block 32200further includes an MIMO decoding block 32210. Operations of the timede-interleaver, cell de-interleaver, constellation demapper, cell to bitmux, and bit de-interleaver blocks included in the third block 32200 maybe different from operations and detailed functions of the correspondingblocks included in the first and second blocks 32000 and 32100, but theblocks included in the third block 32200 are the same as the blocksincluded in the first and second blocks in terms of basic roles.

The MIMO decoding block 32210 may receive output data of the celldeinterleaver as an input with respect to m receiving antenna inputsignal and perform MIMO decoding as an inverse procedure of the MIMOprocessing block. The MIMO decoding block 32210 may perform maximumlikelihood decoding in order to perform maximum decoding performance orsphere decoding for reducing complexity. Alternatively, the MIMOdecoding block 32210 performs MMSE detection or perform iterativedecoding combinationally with the MMSE detection to secure improveddecoding performance.

The fourth block 32300 as a block for processing PLS pre/postinformation may perform SISO or MISO decoding. The fourth block 32300may perform an inverse procedure of the fourth block.

The operations of the time de-interleaver, cell de-interleaver,constellation demapper, cell to bit mux, and bit de-interleaver blocksincluded in the fourth block 32300 may be different from operations anddetailed functions of the corresponding blocks included in the first tothird blocks 32000 to 32200, but the blocks included in the fourth block32300 are the same as the blocks included in the first to third blocksin terms of basic roles.

A shortened/punctured FEC decoder 32310 may perform an inverse procedureof the shortened/punctured FEC encoder block. That is, theshortened/punctured FEC decoder 32310 may perform de-shortening andde-puncturing, and thereafter, FEC decoding data received while beingshortened/punctured according to the length of the PLS data. In thiscase, since the FEC decoder used in the data pipe may be similarly usedeven in the PLS, separate FEC decoder hardware for only the PLS is notrequired, and as a result, system design is easy and efficient coding isavailable.

The aforementioned blocks may be omitted according to an intention of adesigner or substituted by other blocks having a similar or the samefunction.

Consequently, as illustrated in FIG. 32, the demapping and decodingmodule according to the embodiment of the present invention may outputto the output processor the data pipe and the PLS information processedfor each path.

FIGS. 33 and 34 illustrate an output processor according to anembodiment of the present invention.

FIG. 33 illustrates an output processor according to an embodiment ofthe present invention.

The output processor illustrated in FIG. 33 corresponds to theembodiment of the output processor described in FIG. 9. Further, theoutput processor illustrated in FIG. 33 which is used to receive asingle data pipe output from the demapping and decoding module andoutput a single output stream may perform an inverse operation of theinput formatting module.

The output processor of FIG. 33 implements functions, processes, and/ormethods proposed in FIGS. 50, 51, and 53 to be described below.

The output processor illustrated in FIG. 33 may include a BB Descrambler33000, a padding removable block 33100, a CRC-8 decoder block 33200, anda BB frame processor block 33300.

The BB Descrambler block 33000 generates the same PRBS as used at thetransmitting side with respect to an input bit stream and XOR-operatesthe PRBS and the bit stream to perform descrambling.

The padding removable block 33100 may remove a padding bit inserted bythe transmitting side as necessary.

The CRC-8 decoder block 33200 perform CRC decoding of the bit streamreceived from the padding removable block 33100 to check a block error.

The BB frame processor block 33300 may decode information transmitted tothe BB frame header and restore an MP3G-TS, an IP stream (v4 or v6), ora generic stream.

The aforementioned blocks may be omitted according to the intention ofthe designer or substituted by other blocks having a similar or the samefunction.

FIG. 34 illustrates an output processor according to another embodimentof the present invention.

The output processor illustrated in FIG. 34 corresponds to theembodiment of the output processor described in FIG. 9. Further, theoutput processor illustrated in FIG. 34 corresponds to the case ofreceiving multiple data pipes output from the demapping and decodingmodule. Decoding the multiple data pipes may include the case of mergingcommon data which may be commonly applied to a plurality of data pipesand a data pipe associated with the common data and decoding the mergedcommon data and data pipe or the case in which the receiving apparatussimultaneously decodes several services or service components (includinga scalable video service).

The output processor illustrated in FIG. 34 may include the BBdescrambler block, the padding removable block, the CRC-8 decoder block,and the BB frame processor block 33300 similarly to the outputprocessor.

The output processor of FIG. 34 implements functions, processes, and/ormethods proposed in FIGS. 50, 51, and 53 to be described below.

The respective blocks may be different from the blocks described in FIG.33 in terms of the operations and the detailed operations, but therespective blocks are the same as the blocks of FIG. 33 in terms of thebasic role.

A de-jitter buffer block 34000 included in the output processorillustrated in FIG. 34 may compensate a delay arbitrarily inserted atthe transmitting side according to a restored time to output (TTO)parameter for synchronizing the multiple data pipes.

Further, a null packet insertion block 34100 may restore a null packetremoved in the stream by referring to restored deleted null packet (DNP)information and output the common data.

A TS clock regeneration block 34200 may restore detailed timesynchronization of an output packet based on ISCR—input stream timereference information.

A TS recombining block 34300 recombines the common data output from thenull packet insertion block 34100 and the data pipes associated with thecommon data to restore the recombined common data and data pipes to theoriginal MPEG-TS, IP stream (v4 or v6), or generic stream and output therestored MPEG-TS, IP stream (v4 or v6), or generic stream. The TTO, DNP,and ISCR information may be all acquired through the BB frame header.

An in-band signaling decoder block 34400 may restore and output in-bandphysical layer signaling information transmitted through a padding bitfield in each FEC frame of the data pipe.

The output processor illustrated in FIG. 34 performs BB descramblingPLS-pre information and PLS-post information input according to thePLS-pre path and the PLS-post path, respectively and decodes thedescrambled data to restore the original PLS data. The restored PLS datamay transferred to the system controller in the receiving apparatus andthe system controller may provide a required parameter to thesynchronization and demodulation module, the frame parsing module, thedemapping and decoding module, and the output processor module in thereceiving apparatus.

The aforementioned blocks may be omitted according to the intention ofthe designer or substituted by other blocks having a similar or the samefunction.

FIG. 35 illustrates a coding and modulation module according to anotherembodiment of the present invention.

The coding and modulation module illustrated in FIG. 35 may include afirst block 35000 for the SISO scheme, a second block 35100 for the MISOscheme, and a third block 35200 for the MIMO scheme, and a fourth block35300 for processing PLS pre/post information in order to control QoSfor each service or service component transmitted through each datapipe. Further, the coding and modulation module according to theembodiment of the present invention may include blocks for similarly ordifferently processing the respective data pipes according to theintention of the designer as described above. The first to fourth blocks35000 to 35300 illustrated in FIG. 35 may include substantially the sameblocks as the first to fourth blocks.

However, the first to fourth blocks 35000 to 35300 are different fromthe aforementioned first to fourth blocks in that a function of aconstellation mapper block 35010 included in the first to third blocks35000 to 35200 is different from that of the constellation mapper blockincluded in the first to third blocks, and a rotation and I/Ointerleaver block 35020 is included between the cell interleaver and thetime interleaver of the first to fourth blocks 35000 to 35300, and aconfiguration of the third block 35200 for the MIMO scheme is differentfrom that of the third block for the MIMO scheme.

The constellation demapper block 35010 illustrated in FIG. 35 may map aninput bit word to a complex symbol.

The constellation mapper block 35010 illustrated in FIG. 35 may becommonly applied to the first to third blocks 35000 to 35200 asdescribed above.

The rotation and I/O interleaver block 35020 independently interleavesin-phase and quadrature-phase components of respective complex symbolsof cell-interleaved data output from the cell interleaver to output theinterleaved components by the unit of the symbol. The number of inputdata and output symbols of the rotation and I/O interleaver block 35020is two or more and may be changed according to the intention of thedesigner. Further, the rotation and I/O interleaver block 35020 may notinterleave the in-phase components.

The rotation and I/O interleaver block 35020 may be commonly applied tothe first to fourth blocks 35000 to 35300 as described above. In thiscase, whether the rotation and I/O interleaver block 35020 is applied tothe fourth block 35300 for processing the PLS pre/post information maybe signaled through the aforementioned preamble.

The third block 35200 for the MIMO scheme may include a Q-blockinterleaver block 35210 and a complex symbol generator block 35220 asillustrated in FIG. 35.

The Q-block interleaver block 35210 may perform permutation of a paritypart of the FEC-encoded FEC block received from the FEC encoder.Therefore, a parity part of an LDPC H matrix may be made in a cyclicstructure similarly to an information part. The Q-block interleaverblock 35210 permutates sequences of bit blocks having a Q size in theLDPC H matrix and thereafter, performs row-column block interleaving ofthe bit blocks to generate and output a final bit stream.

The complex symbol generator block 35220 may receive the bit streamsoutput from the Q-block interleaver block 35210 and map the received bitstreams to the complex symbol and output the mapped bit streams andcomplex symbol. In this case, the complex symbol generator block 35220may output the symbols through at least two paths. This may be changedaccording to the intension of the designer.

The aforementioned blocks may be omitted according to the intention ofthe designer or substituted by other blocks having a similar or the samefunction.

Consequently, as illustrated in FIG. 35, the coding and modulationaccording to another embodiment of the present invention may output thedata pipe, the PLS-pre information, and the PLS-post informationprocessed for each path to a frame structure module.

FIG. 36 illustrates a demapping and decoding module according to anotherembodiment of the present invention.

The demapping and decoding module illustrated in FIG. 36 corresponds toanother embodiment of the demapping and decoding module described inFIGS. 9 and 32. Further, the demapping and decoding module illustratedin FIG. 36 may perform an inverse operation of the coding and modulationmodule described in FIG. 35.

As illustrated in FIG. 36, the demapping and decoding module accordingto another embodiment of the present invention may include a first block36000 for the SISO scheme, a second block 36100 for the MISO scheme, athird block 36200 for the MIMO scheme, and a fourth block 36300 forprocessing the PLS pre/post information. Further, the demapping anddecoding module according to the embodiment of the present invention mayinclude blocks for similarly or differently processing the respectivedata pipes according to the intention of the designer as describedabove. The first to fourth blocks 36000 to 36300 illustrated in FIG. 36may include substantially the same blocks as the first to fourth blocks32000 to 32300 described in FIG. 32.

However, the first to fourth blocks 36000 to 36300 are different fromthe aforementioned first to fourth blocks in that an I/Q deinterleaverand derotation block 36010 is included between the time deinterleaverand the cell deinterleaver, a function a constellation demapper block36020 included in the first to third blocks 36000 to 36200 is differentfrom the function of the constellation mapper 42030 included in thefirst to third blocks 32000 to 32200 of FIG. 32, and a configuration ofthe third block 36200 for the MIMO scheme is different from that of thethird block 36200 for the MIMO scheme illustrated in FIG. 36.Hereinafter, the same blocks as FIG. 36 will not described and theaforementioned differences will be primarily described.

The I/Q deinterleaver and derotation block 36010 may perform an inverseprocedure of the rotation and I/Q interleaver block 35020 described inFIG. 35. That is, the I/Q deinterleaver and derotation block 36010 maydeinterleave I and Q components I/Q interleaved and transmitted at thetransmitting side and derotate and output the complex symbol having therestored I/Q component again.

The I/Q deinterleaver and derotation block 36010 may be commonly appliedto the first to fourth blocks 36000 to 36300 as described above. In thiscase, whether the I/Q deinterleaver and derotation block 36010 isapplied to the fourth block 36300 for processing the PLS pre/postinformation is may be signaled through the aforementioned preamble.

The constellation demapper block 36020 may perform an inverse procedureof the constellation mapper block 35010 described in FIG. 35. That is,the constellation demapper block 36020 may not perform derotation, butdemap the cell-deinterleaved data.

The third block 36200 for the MIMO scheme may include a complex symbolgenerator block 36210 and a Q-block deinterleaver block 36220 asillustrated in FIG. 36.

The complex symbol parsing block 36210 may perform an inverse procedureof the complex symbol generator block 35220 described in FIG. 35. Thatis, the complex symbol parsing block 36210 may parse the complex datasymbol, and demap the parsed complex data symbol to the bit data andoutput the data. In this case, the complex symbol parsing block 36210may receive the complex data symbols through at least two paths.

The Q-block deinterleaver block 36220 may perform an inverse procedureof the Q-block interleaver block 35210 described in FIG. 35. That is,the Q-block deinterleaver block 36220 may restore the Q-size blocks bythe row-column deinterleaving, restore the permutated sequences of therespective blocks to the original sequences, and thereafter, restore thepositions of the parity bits to the original positions through theparity deinterleaving and output the parity bits.

The aforementioned blocks may be omitted according to the intention ofthe designer or substituted by other blocks having a similar or the samefunction.

Consequently, as illustrated in FIG. 36, the demapping and decodingmodule according to another embodiment of the present invention mayoutput the data pipe and the PLS information processed for each path tothe output processor.

FIG. 37 is a diagram illustrating another structure of the broadcastingsignal transmission apparatus for a next-generation broadcasting servicein accordance with an embodiment of the present invention.

The broadcasting signal transmission apparatus 37000 of FIG. 37 includesboth a normative block and an informative block.

In FIG. 37, blocks indicated by solid lines denote normative blocks.Blocks that may be used when an informative MIMO annex is implemented,that is, informative blocks, are indicated by dotted lines.

The broadcasting signal transmission apparatus in accordance with anembodiment of the present invention includes four major blocks, that is,(1) an input formatting block 37100, (2) a BICM block 37200, (3) aframing & interleaving (FRM/INT) block 37300, and (4) a waveformgeneration block 37400.

The framing & interleaving block 37300 may be represented by a framebuilding block.

A Signal Frequency Network (SFN) dispersion (or distribution) interface37500 is present between the input formatting block 37100 and the BICMblock 37200.

A multiplexing method which may be applied to broadcasting signaltransmission/reception methods proposed in this specification mayinclude two types of method: Time Division Multiplexing (TDM) andLayered Division Multiplexing (LDM) and a method in which the two typesof methods are combined.

The internal block diagram of a broadcasting transmission system for thetwo types of normative multiplexing methods may be implemented simplerthan the internal block diagram of the entire broadcasting transmissionsystem described with reference to FIGS. 1 and 37.

FIG. 38 is a diagram illustrating a simplified TDM broadcastingtransmission system and LDM broadcasting transmission system inaccordance with an embodiment of the present invention.

Specifically, FIG. 38a illustrates an example of the simplified TDMbroadcasting transmission system, and FIG. 38b illustrates an example ofthe simplified LDM broadcasting transmission system.

As illustrated in FIG. 38a , the TDM broadcasting transmission systemincludes four major internal block diagrams. The four major internalblock diagrams include an input formatting block, a Bit Interleaved andCoded Modulation (BICM) block, a framing & interleaving block, and awaveform generation block.

Each of the blocks is described in brief below. Data is inputted to theinput formatting block and formatted therein. The formatted data issubjected to Forward Error Correction (FEC) in the BICM block. Next, thedata is mapped according to constellation mapping.

Furthermore, the data is subjected to interleaving and frame generationin time and frequency domains in the framing & interleaving block. As aresult, a waveform is generated in the waveform generation block andthen output.

As illustrated in FIG. 38b , the LDM broadcasting transmission systemincludes a new block not present in the TDM broadcasting transmissionsystem, that is, an LDM injection block 38100. The LDM broadcastingtransmission system includes two separate input formatting blocks andtwo separate BICM blocks.

The separate blocks (i.e., each of the two input formatting blocks andeach of the two BICM blocks) are applied to each LDM layer.

The separate blocks are combined before framing & interleaving areperformed in the LDM injection block 38100.

Furthermore, a plurality of Radio Frequency (RF) channels is supportedthrough channel bonding.

The Layered Division Multiplexing (LDM) broadcasting system of FIG. 38bis described in more detail.

LDM refers to a constellation superposition technology in which aplurality of data streams is combined in different power levels so thata different modulation and channel coding scheme (MCS) is applied toeach data stream before a signal is transmitted through a single RFchannel.

A 2-layer LDM system is described as an example, for convenience ofdescription.

As illustrated in FIG. 38b , the 2-layer LDM system includes an element(i.e., the LDM injection block 38100) for combining two BICM chainsprior to time interleaving.

Each of the two BICM chains (including an encoded sequence modulated toa constellation) is described as a single layer, but may be representedby a single PLP.

The two BICM layers may be respectively a core layer and an enhancedlayer.

The core layer needs to use a MODCOD combination that is the same as ormore robust than the enhanced layer.

Each of the core layer and the enhanced layer may use different FECcoding and constellation mapping.

In general, the core layer and the enhanced layer may have the same codelength, but have different code rates and constellations.

The core layer and enhanced layer are combined in the LDM injectionblock (illustrated in FIG. 38b ).

Furthermore, an injection level controller is used to reduce power ofthe enhanced layer compared to the core layer in order to outputtransmission energy that will achieve a specific bit rate.

An injection level (of the signal of the enhanced layer compared to thesignal of the core layer) is a transmission parameter that enables thedistribution of transmission power between the two layers.

The transmission robustness of each of the two layers may be changed bydiversifying the injection level.

Furthermore, signals combined through the LDM injection block 38100 arenormalized in a power normalizer block after power of all the signals iscombined.

FIG. 39 illustrates a framing & interleaving block in accordance with anembodiment of the present invention.

The framing & interleaving block may be represented by a frame buildingblock.

The framing & interleaving block 39000 includes three parts, that is, atime interleaving block 39100, a framing block 39200, and a frequencyinterleaving block 39300.

An input to the time interleaving and framing block 39100 may include aplurality of PLPs (or M-PLPs).

In contrast, the output of the framing block 39200 includes OFDM symbolsarranged in frames. A frequency interleaver operates on OFDM symbols.

The framing block 39200 output inputs as one or more PLPs and outputsymbols. In this case, the inputs denote data cells.

Furthermore, the framing block generates one or more special symbolswell known as preamble symbols.

The special symbols undergo the same processing in the waveformgeneration block.

FIG. 40 is a diagram illustrating an example of an ATSC 3.0 framestructure to which an embodiment of the present invention may beapplied.

Referring to FIG. 40, the ATSC 3.0 frame 40000 includes three parts,that is, (1) a bootstrap 40100, (2) a preamble 40200, and (3) a datapayload 40300.

Each of the three parts includes one or more symbols.

Specifically, preamble symbols transmit the L1 signaling data ofsubsequent data symbols.

That is, the L1 signaling data includes information related to datasymbols, and the data symbols are subsequent to (or placed after) the L1signaling data.

The preamble symbols are directly generated after a bootstrap and beforespecific data symbols.

The data symbols transmit data within a frame.

The data symbols are directly generated after the preamble symbols andbefore a next bootstrap.

L1 signaling provides information required to configure (or set)physical layer parameters.

The term “L1” refers to Layer-1 and refers to the lowest layer of theISO 7 layer model.

The L1 signaling is included in a preamble.

The L1-signaling includes two parts, that is, (1) L1-static and (2)L1-dynamic.

L1-static completes a frame, transmits the most basic signalinginformation about a static system, and also defines parameters requiredto decode L1-dynamic.

L1-dynamic materializes information and data context required to decodeL1-dynamic.

The length of L1-static signaling is fixed to 200 bits, and the lengthof L1-dynamic signaling may be defined in various ways.

Table 34 is an example of an L1-static information format. Parameters ofL1-static are previously determined to be always “LiS_.”

TABLE 34 SYNTAX NUNBER OF BITS FORMAT . . . L1S_frequency 1 interleaver. . .

The bootstrap 40100 is described in more detail.

The bootstrap provides a universal entry point to an ATSC waveform.

The bootstrap is defined as fixed elements (e.g., a sampling rate, asignal bandwidth, a subcarrier spacing, and a time domain structure)known to all the broadcasting signal reception apparatuses.

In a common structure of the bootstrap, a bootstrap signal is placedahead of a post-bootstrap waveform.

The post-bootstrap waveform means the remaining parts of a frame.

That is, a preamble may be placed after the bootstrap.

The bootstrap includes a plurality of symbols and starts from asynchronization symbol.

The synchronization symbol is placed at the start of each frame sectionso that service discovery, coarse synchronization, frequency offsetestimation, and initial channel estimation are possible.

The bootstrap includes four symbols including an (initial)synchronization symbol.

The signaling field of a bootstrap symbol 1 includes eas_wake_upinformation, system_bandwidth information, and min_time_to_nextinformation.

The eas_wake_up information refers to information indicating whetheremergency is present or not.

The system_bandwidth information is information about a system bandwidthused for the post-bootstrap part of a current PHY layer frame.

The min_time_to_next information is information about a minimum timeinterval up to a next frame in which the major version number and minorversion number of a current frame are identically matched.

The signaling field of a bootstrap symbol 2 includes bsr_coefficientinformation.

The bsr_coefficient information is information indicating that a samplerate post-bootstrap (of a current PHY layer frame) is (N+16)*0.384 MHz.

In this case, N is a value of 0 to 80 which is signaled.

The signaling field of the bootstrap symbol 2 includespreamble_structure information.

The preamble_structure information is indicative of information thatsignals the structure of one or more RF symbols placed after the lastbootstrap symbol.

Frequency Interleaving (FI)

Frequency interleaving is described in more detail.

FI may be used as a team that means frequency interleaving or afrequency interleaver.

FI operates in a single OFDM symbol, and is used to separate errorbursts generated in a frequency domain.

Whether FI is used or not may be selected by the signaling of anL1S_frequency interleaver.

An L1S_frequency interleaver field is included in the preamble of theATSC 3.0 frame as described above.

Input cells of FI (i.e., the output cells of the framing block) aredefined as X_(m,l)=(x_(m,l,0), x_(m,l,1), x_(m,l,2), . . . , x_(m,l,N)_(data) ⁻¹).

x_(m,l,q) is indicative of the cell index q of the symbol l (l=0, . . ., L_(F)−1) of a frame m.

N_(data) is indicative of the number of active data carriers of a singlesymbol. N_(data) is set as N_(data)=C_(N) with respect to a normalsymbol, represented by N_(data)=C_(FS) with respect to a frame startsymbol, and represented by N_(data)=C_(FC) with respect to a frameclosing symbol.

FI processes the output vector, that is, X_(m,l)=(x_(m,l,0), x_(m,l,1),x_(m,l,2), . . . , x_(m,l,N) _(data) ⁻¹), of the frame builder (or theframing & interleaving block).

x_(m,l,q) is indicative of the cell index q of an OFDM symbol of theframe m.

Each FI includes a basic interleaving sequence (or main interleavingsequence) having wire permutation and a symbol offset generator havingan offset addition block.

The address check block authenticates a generated interleaving addressvalue, and the offset addition block is placed after an address checkblock.

The address check block may be called a memory index check block or amemory address check block.

The symbol offset generator may be accomplished for each symbol pair.

For example, the symbol offset value is constant with respect to twosequential symbols (2l and 2l+1).

A Frequency Interleaving (FI) procedure and a method of supporting aFrequency Interleaver (FI) on/off operation mode proposed in thisspecification are described below.

On/Off Operation Mode of Frequency Interleaver (FI)

First, the method of supporting an FI on/off operation mode proposed inthis specification is described with reference to related drawings.

FIG. 41 is a diagram illustrating another example of the frame buildingblock of FIG. 7.

The frame building block 41000 of FIG. 41 may be an internal blockdiagram indicative of another example of the framing & interleavingblock of FIG. 39.

That is, FIG. 41 illustrates an example of the frame building block (orframing & interleaving block) including a random frequency interleavercorresponding to the block interleaver 41100 of a future broadcastingsystem proposed in this specification.

The block interleaver 41110 may be interpreted as being a meaning, suchas a frequency interleaver or a random frequency interleaver, or may berepresented by a frequency interleaver or a random frequencyinterleaver.

The random frequency interleaver of FIG. 41 obtains an additionalfrequency diversity gain by interleaving cells within a transmissionblock, that is, the unit of a transmission frame, based on a frequencyaxis.

In particular, this specification provides an operation of frequencyinterleaving for applying a different interleaving seed to each OFDMsymbol in the broadcasting signal transmission apparatus (Specifically,in the frequency interleaver) and applying a different interleaving seedto each frame including a plurality of OFDM symbols.

As illustrated in FIG. 41, this specification provides the method ofsupporting the on/off operation mode of the random frequencyinterleaver.

The method of supporting the on/off operation mode of FI is described indetail below with reference to FI mode (FI_MODE) information 41200 andFIG. 42.

FIG. 42 is a diagram illustrating an example of a preamble format towhich an embodiment of the present invention may be applied.

As illustrated in FIG. 42, the preamble 42000 includes frequencyinterleaver mode (FI_MODE) information 42100.

A preamble is included in the aforementioned ATSC 3.0 frame and isplaced after a bootstrap and before a data payload.

For the structure of the ATSC 3.0 frame and a related descriptionthereof, reference may be made to FIG. 40.

That is, the FI_MODE information may be included in L1 signalingincluded in the preamble.

The L1-signaling may be divided into two parts, that is, L1-static andL1-dynamic, as described with reference to FIG. 40.

In this case, the FI_MODE information may be included in the L1-staticand/or the L1-dynamic.

The frequency interleaver (FI) mode (FI_MODE) information included inthe preamble is indicative of information indicating whether FI isavailable.

Whether FI is available may be indicated by on or off.

That is, the FI mode information is information indicating whether FIhas been on or off and may be represented by 1 bit.

If the FI mode has been set as on (or if the FI mode is indicative ofon), data cells output by a cell mapper is subjected to frequencyinterleaving in each OFDM symbol through FI.

The FI mode information may be represented by FI mode signaling.

For example, if the FI mode information has been set to “1”, it mayindicate that FI has been on. On the contrary, if the FI modeinformation has been set to “0”, it may indicate that the FI has beenoff.

More specifically, the FI mode information may be transmitted through L1signaling within a frame.

In this case, a preamble symbol(s) transmits L1 signaling data for adata symbol(s) subsequent to the preamble symbol(s).

The preamble symbol(s) is placed after a bootstrap and placed beforedata symbol(s).

The L1 signaling provides required information for configuring physicallayer parameters, and L1 means Layer-1 corresponding to the lowest layerof the ISO 7 layer model.

Furthermore, the L1 signaling is included in a preamble, and includestwo parts (i.e., L1-static and L1-dynamic).

FIG. 43 is a diagram illustrating another internal block diagram of theframe parsing block of FIG. 31.

That is, FIG. 43 illustrates an example of a frame parsing blockincluding a random frequency deinterleaver corresponding to the blockdeinterleaver 43100 of a future broadcasting system proposed in thisspecification.

The block deinterleaver 43100 may be interpreted as a meaning, such as afrequency deinterleaver or a random frequency deinterleaver, or may berepresented by a frequency deinterleaver or a random frequencydeinterleaver.

As illustrated in FIG. 43, FI mode (FI_MODE) information or FI modesignaling refers to information indicative of an on or off operationmode of FI, as described with reference to FIG. 42.

That is, FI mode information 43200 indicates whether FI is available.

The FI mode information is included in a frame and is specificallyincluded in the preamble of the frame.

Furthermore, the FI mode information is included in the L1 signaling ofthe preamble.

The L1-signaling may be divided into two parts, that is, L1-static andL1-dynamic. As described with reference to FIG. 40, the FI_MODEinformation may be included in the L1-static and/or the L1-dynamic.

In this case, if the FI_MODE information is indicative of “on” of FIMODE, the broadcasting signal reception apparatus performs frequencydeinterleaving through a frequency deinterleaver, that is, a processopposite a frequency interleaving process performed by the frequencyinterleaver of a broadcasting signal transmission apparatus, so that theoriginal data sequence is obtained.

As described with reference to FIGS. 42 and 43, the operation of theFI_MODE information proposed in this specification corresponds toessential information in order to support Frequency DivisionMultiplexing (FDM) in a broadcasting system.

If a broadcasting system supports an FDM method, the broadcasting signaltransmission apparatus may transmit PLPs and/or data for each specificfrequency band.

Accordingly, if PLPs or data are transmitted according to FDM, FIbecomes off in order to reduce performance deterioration which may begenerated because PLPs or data is transmitted through a poor frequencyedge part in a neighbor channel (or neighbor frequency band).

Specifically, when PLPs or data having high importance (or high quality)is transmitted using a specific frequency band (according to the FDMmethod), if the FI operation is performed, the PLPs or data are spreadinto the entire specific frequency band, so performance deterioration isgenerated in a frequency edge part that may be influenced by a neighborchannel.

Accordingly, there is an advantage in that FDM can be supported becausean FI operation is made off through the operation of the FI modeinformation that makes on or off the FI operation proposed in thisspecification.

Frequency Interleaving (FI) Method

A frequency interleaving method proposed in this specification isdescribed in detail below with reference to related drawings.

The frequency interleaving method to be described below is performedwhen the FI mode of an FI mode information value included in thepreamble has been “on.”

As described above, the basic function of the cell mapper of FIG. 7 isto map the data cells of respective DPs (or PLPs) or PLS data to thearrays of active OFDM cells respectively corresponding to the OFDMsymbols of a single signal frame.

As described above, the block interleaver may operate in a single OFDMsymbol and may provide frequency diversity by randomly interleavingcells received from the cell mapper.

That is, an object of the block interleaver operating in a single OFDMsymbol is to provide frequency diversity by randomly interleaving datacells received from the frame structure module (or the frame buildingmodule or the framing & interleaving module).

In order to obtain a maximum interleaving gain from a single signalframe (or a single frame), another interleaving seed is used in eachOFDM pair including two sequential OFDM symbols.

The block interleaver of FIG. 41 may obtain an additional diversity gainby interleaving cells within a transport block, that is, the unit of asignal frame.

As described above, the block interleaver may be called a frequencyinterleaver or a specific frequency interleaver, which may be changeddepending on a designer's intention.

In an embodiment, the block interleaver in accordance with an embodimentof the present invention may apply a different interleaving seed to atleast one OFDM symbol or apply a different interleaving seed to a frameincluding a plurality of OFDM symbols.

The frequency interleaving method may be called random frequencyinterleaving (random FI).

Furthermore, in an embodiment, the random FI may be applied to a superframe structure including a plurality of signal frames each including aplurality of OFDM symbols.

That is, the frequency interleaver of the broadcasting signaltransmission apparatus or the broadcasting signal transmission apparatusproposed in this specification may obtain frequency diversity in such away as to perform random FI by applying a different interleaving seed(or interleaving pattern) to each OFDM symbol or at least one OFDMsymbol, that is, every two paired OFDM symbols (i.e., pair-wise OFDMsymbol).

Furthermore, the frequency interleaver in accordance with an embodimentof the present invention may obtain additional frequency diversity insuch a way as to perform random FI by applying a different interleavingseed to each signal frame.

Accordingly, the broadcasting signal transmission apparatus or thefrequency interleaver proposed in this specification may have aping-pong frequency interleaver structure for performing frequencyinterleaving for each pair of sequential pair-wise OFDM symbols usingtwo memory banks.

The interleaving operation of the frequency interleaver proposed in thisspecification may be hereinafter called pair-wise symbol FI (orpair-wise FI) or ping-pong FI (ping-pong interleaving).

The aforementioned interleaving operation corresponds to an embodimentof random FI, and may be changed depending on a designer's intention.

Even-numbered pair-wise OFDM symbols and odd-numbered pair-wise OFDMsymbols may be non-sequentially interleaved through different FI memorybanks.

Furthermore, the frequency interleaver may simultaneously performreading and writing operations on a pair of sequential OFDM symbolsinputted to each memory bank using a random interleaving seed. Adetailed operation of the frequency interleaver is described later.

Furthermore, in this specification, an embodiment in which aninterleaving seed is basically changed for each pair of OFDM symbols maybe used as a logical frequency interleaving operation for interleavingall OFDM symbols within a super frame rationally and efficientlyinterleaving.

In an embodiment of this specification, the interleaving seed may begenerated by a specific random generator or a random generator includinga combination of several random generators.

Furthermore, in an embodiment of this specification, for an efficientchange of an interleaving seed, various interleaving seeds may begenerated by cyclically shifting a single main interleaving seed.

In this case, the cyclic-shifting rule may be hierarchically defined bytaking into consideration an OFDM symbol and a signal frame unit. Thismay be changed depending on a designer's intention, and the detailedcontents of the cyclic-shifting rule are described later.

Furthermore, the broadcasting signal reception apparatus proposed inthis specification may perform a process opposite the aforementionedrandom frequency interleaving process.

In this case, the frequency deinterleaver of the broadcasting signalreception apparatus or the broadcasting signal reception apparatus inaccordance with an embodiment of the present invention may performdeinterleaving on sequential input OFDM symbols using a single piece ofmemory without using a ping-pong structure using two pieces of memory.Accordingly, the frequency deinterleaver can increase use efficiency ofmemory.

Furthermore, reading and writing operations are still required in thefrequency deinterleaver and may be called a single memory deinterleavingoperation.

Accordingly, the single memory deinterleaving method is very efficientin terms of memory use.

FIG. 44 is a diagram illustrating the operation of the frequencyinterleaver in accordance with an embodiment of the present invention.

FIG. 44 illustrates the basic operation of the frequency interleaverusing two memory banks in the broadcasting signal transmissionapparatus. This enables a single memory deinterleaving operation in thebroadcasting signal reception apparatus.

As described above, the frequency interleaver proposed in thisspecification may can a ping-pong interleaving operation.

In general, the ping-pong interleaving operation may be achieved by twomemory banks.

In the FI operation proposed in this specification, two memory banksrelate to respective pair-wise OFDM symbols.

A maximum memory (ROM) size of frequency interleaving corresponds toabout twice a maximum FFT size.

In the broadcasting signal transmission apparatus, an increase of theROM size tends to be less important compared to the broadcasting signalreception apparatus.

As described above, even-numbered pair-wise OFDM symbols andodd-numbered pair-wise OFDM symbols may be non-sequentially interleavedthrough different FI memory banks.

That is, a first (having an even index) pair-wise OFDM symbol isinterleaved in a first memory bank, whereas a second (having an oddindex) pair-wise OFDM symbol is interleaved in a second memory bank.

A single interleaving seed is used in each of pair-wise OFDM symbols.

Two OFDM symbols are sequentially interleaved based on the interleavingseed and the reading-writing (or writing-reading) operation.

Reading-writing operations proposed in this specification may beachieved at the same time without a collision.

As illustrated in FIG. 44, the frequency interleaver may include a DEMUX44000, two memory banks (i.e., a memory bank-A 44100 and a memory bank-B44200), and a MUX 44300.

First, the frequency interleaver may perform demultiplexing processingon sequential input OFDM symbols through the DEMUX 44000 for pair-wiseOFDM symbol FI.

Thereafter, the frequency interleaver performs reading-writing FIoperations on each of the memory bank A and the memory bank B using asingle interleaving seed.

As illustrated in FIG. 44, the two memory bank-A and bank-B are used foreach OFDM symbol pair.

A second (having an odd index) OFDM symbol pair is interleaved in thememory bank-B, whereas a first (having an even index) OFDM symbol pairis interleaved in the memory bank-A. The operations in the memory bank-Aand bank-B may be exchanged.

Thereafter, the frequency interleaver may perform multiplexingprocessing on ping-pong FI outputs through the MUX 44300 in order totransmit sequential OFDM symbols.

FIG. 45 illustrates the basic switch model of MUX and DEMUX methods inaccordance with an embodiment of the present invention.

FIG. 45 illustrates simple operations of the DEMUX and the MUX appliedto the inputs and outputs of the memory bank-A and bank-B in theaforementioned ping-pong FI structure.

The DEMUX and the MUX may perform control so that respective sequentialinput OFDM symbols are interleaved and may perform control so that apair of output OFDM symbols is transmitted.

A different interleaving seed is used in each OFDM pair.

As illustrated in FIG. 45, the DEMUX and the MUX output an FI input andan FI output, respectively, according to Equation 12 below.

s=j mod 2  [Equation 12]

In Equation 12, mod denotes modulo operation for j=0, 1, . . . ,N_(sym)−1, and N_(sym) denotes the number of OFDM symbols within asingle frame.

Reading-writing operations of frequency interleaving in accordance withan embodiment of the present invention is described below.

The frequency interleaver may select or use a single interleaving seedin each of first and second OFDM symbols and may use an interleavingseed in writing and reading operations.

That is, the frequency interleaver can effectively perform interleavingusing an operation of writing a single selected random interleaving seedwith respect to the first OFDM symbol of pair-wise OFDM symbols andusing a reading operation with respect to the second OFDM symbol of thepair-wise OFDM symbols.

Accordingly, two different interleaving seeds may look as if they arerespectively applied to two OFDM symbols.

The detailed contents of reading-writing operations proposed in thisspecification are as follows.

The frequency interleaver in accordance with an embodiment of thepresent invention may randomly perform writing on memory (depending onan interleaving seed) with respect to a first OFDM symbol and thenperform linear reading.

The frequency interleaver in accordance with an embodiment of thepresent invention may simultaneously perform linear writing on memoryunder the influence of the linear reading operation for the first OFDMsymbol with respect to a second OFDM symbol.

Thereafter, the frequency interleaver in accordance with an embodimentof the present invention may randomly perform reading based on aninterleaving seed.

As described above, the broadcasting signal transmission apparatus inaccordance with an embodiment of the present invention may sequentiallytransmit a plurality of signal frames on the time axis.

In an embodiment of the present invention, a set of signal framestransmitted for a specific time may be called a super frame.

Accordingly, a single super frame may include N signal frames, and eachof the signal frames may include a plurality of OFDM symbols.

FIG. 46 illustrates the operation of a memory bank in accordance with anembodiment of the present invention.

As described with reference to FIGS. 44 and 45, the two memory bank-Aand bank-B may apply a random interleaving seed, generated through theaforementioned process, to respective pair-wise OFDM symbols.

Furthermore, each of the memory bank-A and bank-B may changeinterleaving seeds for each pair-wise OFDM symbol.

In each of the aforementioned memory bank-A and bank-B, a method ofchanging an interleaving seed is described in more detail with referenceto Equations 13 to 16.

Equation 13 illustrates an equation related to the random interleavingseed of a first OFDM symbol, that is, an OFDM symbol that satisfies (jmod 2)=0 of an i-th OFDM symbol pair.

$\begin{matrix}{{{F_{j}\left( {C_{j}(k)} \right)} = {X_{j}(k)}},{{{where}\mspace{14mu} {C_{j}(k)}} = {\left( {{T(k)} + S_{\lfloor\frac{j}{2}\rfloor}} \right)\mspace{11mu} {mod}\mspace{11mu} N_{data}}}} & \left\lbrack {{Equation}\mspace{14mu} 13} \right\rbrack\end{matrix}$

In Equation 13, i=0, 1, . . . , N_(sym), k=0, 1, . . . , N_(data).

N_(data) denotes the number of active data carriers within a singlesymbol.

Equation 13 is an equation indicative of an output value X_(j)(k) outputby performing frequency interleaving on a j-th pair-wise OFDM symbol inFI using an interleaving sequence corresponding to C_(j)(k). In Equation13, C_(j)(k) may also be represented by H_(j)(k).

T(k) denotes a main interleaving seed (or basic interleaving seed)generated by a random generator used in main FI (or basic FI).

T(k) is a random sequence and may be interpreted as having the sameconcept as a main random interleaving sequence, a basic randominterleaving sequence, or a single interleaving seed.

The random sequence may be generated by a random interleaving sequencegenerator or a random main sequence generator.

T(k) may be defined as Equation 14.

T(k)=(i mod 2)2^(N) ^(r) ⁻¹  [Equation 14]

Furthermore, S_(└j/2┘) denotes a random symbol offset generated by arandom generator used in a j-th pair-wise OFDM symbol.

That is, S_(└j/2┘) is a symbol offset, may also be called a cyclicshifting value, and may be generated based on a sub-Pseudo-Random BinarySequence (PRBS). The detailed contents of the symbol offset aredescribed later.

S_(└j/2┘) may be defined as Equation 15.

$\begin{matrix}{S_{\lfloor\frac{j}{2}\rfloor} = {\sum\limits_{j = 0}^{N_{r} - 1}{G_{\lfloor\frac{j}{2}\rfloor}\left\lceil j \right\rceil 2^{j}}}} & \left\lbrack {{Equation}\mspace{14mu} 15} \right\rbrack\end{matrix}$

In Equations 14 and 15, l=0, l<L_(F), and l=1+2 are satisfied.

Equation 16 is an equation related to the random interleaving seed of asecond OFDM symbol, that is, an OFDM symbol that satisfies (j mod 2)=1of an i-th OFDM symbol pair.

F _(j)(k)=X _(j)(C _(j)(k))  [Equation 16]

In Equation 16, i=0, 1, . . . , N_(sym), k=0, 1, . . . , and N_(data).

Equation 16 is an equation indicative of an output value X_(j)(k) outputby performing frequency interleaving on a j-th pair-wise OFDM symboloutput according to Equation 13 in FI using an interleaving seedcorresponding to C_(j)(k).

In Equation 16, C_(j)(k) is the same as the random interleaving seedused in the first OFDM symbol of Equation 13.

The random generator of Equations 13 and 16 is a random interleavingsequence generator. The random interleaving sequence generator may beincluded in the frequency interleaver 7020.

In each of the memory bank-A and bank-B, an interleaving process for anOFDM symbol pair has been described above, and uses a singleinterleaving seed.

Available data cells, that is, cells output by the cell mapper, areinterleaved in a single OFDM symbol O_(m,l)

O_(m,l) may be defined as in Equation 17.

The data cells O_(m,l) output by the cell mapper denote data cellsinputted to FI.

O _(m,l) =[X _(m,l,0) , . . . ,X _(m,l,p) , . . . ,X _(m,l,N) _(data) ⁻¹],l=0, . . . ,N _(sym)−1  [Equation 17]

In Equation 17, X_(m,l,p) denotes the p-th cell of an 1-th OFDM symbolin an m-th frame, and N_(data) denotes the number of data cells (orframe signaling symbols, normal data, or frame edge symbols).

Furthermore, interleaved data cells P_(m,l) are defined as in Equation18.

The interleaved data cells denote a signal output through FI.

P _(m,l) =[v _(m,l,0) , . . . ,v _(m,l,N) _(data) ⁻¹ ],l=0, . . . ,N_(sym)−1  [Equation 18]

In the aforementioned memory banks, interleaving using interleavingseeds (or interleaving sequences) may be represented as in Equationsbelow.

Equations 18 and 19 may be interpreted as having the same meaning asEquations 13 and 16.

That is, Equations 13 and 16 denote mathematical expressions of aprocess of applying a random interleaving sequence (or seed), generatedthrough the aforementioned logical FI structure, to an OFDM symbol pair.

Equation 18 denotes an equation related to the random interleaving seedof a first OFDM symbol, that is, an OFDM symbol that satisfies (j mod2)=0 of an i-th OFDM symbol pair.

V _(m,l,H) _(l) _((p)) =x _(m,l,p)  [Equation 18]

In Equation 18, l=0, 1, . . . , N_(sym)−1, and p=0, 1, . . . ,N_(data)−1.

H_(l)(p) denotes an interleaving address or an interleaving seedgenerated by a random generator.

For H_(l)(p) or C_(l)(p), reference is made to the aforementionedcontents.

Equation 19 denotes an equation related to the random interleaving seedof a second OFDM symbol, that is, an OFDM symbol that satisfies (j mod2)=1 of an i-th OFDM symbol pair.

v _(m,l,p) =x _(m,l,H) _(l) _((p))  [Equation 19]

In Equation 19, l=0, 1, . . . , N_(sym)−1, and p=0, 1, . . . ,N_(data)−1.

A maximum value of N_(data) is represented by N_(max), and N_(max) isdifferently defined depending on each FFT mode.

OFDM symbol pairs interleaved for the OFDM symbol pairs in therespective memory bank-A and bank-B are illustrated in Equation 18 andEquation 19.

H_(j)(k) is the interleaving address of an interleaving seed generatedby a random interleaving sequence generator with respect to each FFTmode.

The structure of the random interleaving sequence generator is describedlater.

As described above, an object of the frequency interleaver operating ina single OFDM symbol which is proposed in this specification is toprovide frequency diversity by randomly interleaving data cells.

In order to obtain a maximum interleaving gain in a single frame, adifferent interleaving seed is used in each OFDM symbol pair includingtwo sequential OFDM symbols.

As described with reference to Equation 13 and Equation 16, a differentinterleaving seed may be generated based on an interleaving addressgenerated by a random interleaving sequence generator.

Furthermore, a different interleaving seed may be generated based on acyclic shift value as described above.

That is, a different interleaving address used in each symbol pair maybe generated using a cyclic shifting value in each OFDM pair.

As described above, the OFDM generation block may perform FFT transformon input data inputted to the OFDM generation block. Accordingly, in anembodiment, the operation of the frequency interleaver having a randominterleaving sequence generator is described.

The random interleaving sequence generator may also be called aninterleaving address generator and may be changed depending on adesigner's intention.

The random interleaving sequence generator may include a first generatorand a second generator.

The first generator is used to generate a main (or basic) interleavingseed, and the second generator is used to generate a symbol offset.

Accordingly, the first generator may be represented by a random main (orbasic) sequence generator, and the second generator may be representedby a random symbol offset generator.

The names of the first generator and the second generator may be changeddepending on a designer's intention, and the operations of the firstgenerator and the second generator are described in more detail.

Each of the random generators (i.e., the first generator and the secondgenerator) includes a spreader and a randomizer. The spreader and therandomizer function to assign a spreading effect and a random effect,respectively, when an interleaving sequence is generated.

In this case, the (cell) spreader operates using an n-bit upper part ofall bits and may operate as a multiplexer (MUX, n-bit toggling) based ona look-up table.

The randomizer operates through a PN generator and operates so that itprovides full randomness upon interleaving.

The randomizer may represent a PN generator, and may be replaced with arandom PN generator.

A random symbol offset generator operating for each OFDM symbol pairoutputs a symbol offset value required when an interleaving sequence iscyclically shifted.

A modulo operator mod N_(max) within the random symbol offset generatoroperates when it exceeds N_(data).

A memory index check block functions to control an output memory indexvalue by repeatedly driving the spreader and the randomizer so that theoutput memory index value does not exceed N_(data) without using (i.e.,by neglecting) the output memory index value if a generated memory indexvalue is greater than N_(data) and

The memory index check block may be called a memory address check blockor an address check block.

As described above, the FFT size in accordance with an embodiment of thepresent invention may be 1 K, 2 K, 4 K, 8 K, 16 K, 32 K, or 64 K and maybe changed depending on a designer's intention.

Accordingly, interleaving seeds (or the main interleaving seeds) may bevarious based on an FFT size.

FIG. 47 is a diagram illustrating a frequency interleaving process inaccordance with an embodiment of the present invention.

The broadcasting signal reception apparatus in accordance with anembodiment of the present invention may perform a process opposite theaforementioned frequency interleaving process using a single piece ofmemory.

FIG. 47 is a diagram illustrating a single memory frequencydeinterleaving (FDI) process for sequential OFDM symbol inputs.

FDI denotes an abbreviation of frequency deinterleaving or a frequencydeinterleaver.

A frequency deinterleaving operation basically complies with a processopposite the frequency interleaving operation.

Additional processing is not required for the use of a single piece ofmemory for the frequency deinterleaving operation.

When pair-wise OFDM symbols illustrated on the left of FIG. 47 aresequentially inputted, the broadcasting signal reception apparatus mayperform the aforementioned reading and writing operations using a singlepiece of memory, as illustrated on the right of FIG. 47.

In this case, the broadcasting signal reception apparatus may generate amemory index (or memory address) and perform frequency interleaving(reading and writing) corresponding to a process opposite frequencyinterleaving (writing and reading) performed by the broadcasting signaltransmission apparatus.

A gain is obtained using the pair-wise ping-pong interleaving structureproposed in this specification.

FIG. 48 illustrates a conceptual diagram of frequency interleavingapplied to a single super frame in accordance with an embodiment of thepresent invention.

A frequency interleaver in accordance with an embodiment of the presentinvention may change interleaving seeds for each pair-wise OFDM symbolin a single signal frame (i.e., during a section up to a point at whicha symbol index is reset) and may change interleaving seeds so that theinterleaving seeds are used only in one (i.e., during a section up to apoint at which a frame index is reset) of all the frames.

As a result, the frequency interleaver in accordance with an embodimentof the present invention may change interleaving seeds in a super frame(i.e., during a section up to a point at which a super frame index isreset).

Accordingly, the frequency interleaver in accordance with an embodimentof the present invention can interleave all OFDM symbols within a superframe rationally and efficiently.

FIG. 49 is a diagram illustrating the logical operation mechanism offrequency interleaving applied to a single super frame proposed in thisspecification.

FIG. 49 illustrates parameters related to the logical operationmechanism of a frequency interleaver for effectively changinginterleaving seeds to be used in the single super-frame described withreference to FIG. 48.

As described above, in an embodiment of the present invention, variousinterleaving seeds may be efficiently generated by cyclically shifting asingle main interleaving seed by a specific offset.

As illustrated in FIG. 49, in an embodiment, a different interleavingseed may be generated by differently generating the specific offset foreach frame and for each pair-wise OFDM symbol. The logical operationmechanism is described below.

A lower block 49100 of FIG. 49, that is, a frequency interleaverproposed in this specification may randomly generate a frame offset foreach frame using an input frame index. The frame offset in accordancewith an embodiment of the present invention may be generated by a frameoffset generator included in a frequency interleaver.

In this case, a frame offset that may be applied to each frame isgenerated with respect to each signal frame within each super frameidentified based on a super frame index when the super frame index isreset.

As illustrated in a block 49200 in the middle of FIG. 49, the frequencyinterleaver may randomly generate a symbol offset to be applied to eachof OFDM symbols included in each signal frame using an input symbolindex.

The symbol offset may be generated by a symbol offset generator includedin a frequency interleaver. In this case, when a frame index is reset,the symbol offset of each OFDM symbol is generated with respect tosymbols within each signal frame identified based on a frame index.

Furthermore, the frequency interleaver may generate various interleavingseeds by cyclically shifting a main interleaving seed by a symbol offsetwith respect to each OFDM symbol.

Thereafter, as illustrated in a block 49300 on the upper side of FIG.49, the frequency interleaver may perform random FI on cells included ineach OFDM symbol using an input cell index. Random FI parameters inaccordance with an embodiment of the present invention may be generatedby a random FI generator included in the frequency interleaver.

In FIG. 49, π_(frame) denotes a random frame offset used in an i-thframe, π_(symbol)(j,i) denotes the symbol offset of the j-th symbol ofan i-th frame generated by a random symbol offset generator, andπ_(cell)(k,j,i) denotes the cell offset of the k-th cell of the j-thsymbol of an i-th frame generated by a random generator.

Furthermore, N_(frame) denotes the number of frames within a singlesuper frame, N_(sym) denotes the number of OFDM symbols within a singleframe, and N_(cell) denotes the number of cells within a single OFDMsymbol.

FIG. 50 illustrates the equation of the logical operation mechanism offrequency interleaving applied to a single super frame in accordancewith an embodiment of the present invention.

Specifically, FIG. 50 illustrates the relationship between a frameoffset parameter, a symbol offset parameter, and the parameter of arandom FI applied to a cell included in each OFDM symbol.

Referring to FIG. 50, g_(frame) is a random frame offset generator usedin a frame interleaver, g_(sym) is a random symbol offset generator usedin a symbol interleaver, and g_(cell) is a random generator used in acell interleaver.

π_(frame)(i) denotes the frame offset of an i-th frame generated by therandom frame offset generator, π_(symbol)(j,i) denotes the symbol offsetof the j-th symbol of an i-th frame generated by the random symboloffset generator, and π_(cell)(k,j,i) denotes the cell offset of thek-th cell of the j-th symbol of an i-th frame generated by the randomgenerator.

The symbol offset and the cell offset are described in more detail withreference to FIG. 51 to be described later.

As illustrated in FIG. 50, an offset to be used in each OFDM symbol maybe generated through the hierarchical structure of the aforementionedframe offset generator and the aforementioned symbol offset generator.In this case, the frame offset generator and the symbol offset generatormay be designed using a specific random generator.

FIG. 51 is a diagram illustrating the logical operation mechanism offrequency interleaving applied to a single signal frame in accordancewith an embodiment of the present invention.

FIG. 51 illustrates parameters related to the logical operationmechanism of a frequency interleaver for effectively changinginterleaving seeds to be used in the single signal frame described withreference to FIG. 48.

As described above, various interleaving seeds may be efficientlygenerated by cyclically shifting a single main interleaving seed by aspecific symbol offset.

As illustrated in FIG. 51, in an embodiment of the present invention, adifferent interleaving seed may be generated by differently generating asymbol offset for each pair-wise OFDM symbol.

In this case, the symbol offset is differently generated for eachpair-wise OFDM symbol using a specific random symbol offset generator.

The logical operation mechanism is described below.

As illustrated in a block 51100 placed on the lower side of FIG. 51, afrequency interleaver may randomly generate a symbol offset to beapplied to each of OFDM symbols included in each signal frame using aninput symbol index.

The symbol offset (or random symbol offset) may be generated by aspecific random generator (or symbol offset generator) included in thefrequency interleaver.

In this case, when a frame index is reset, the symbol offset of eachOFDM symbol is generated with respect to OFDM symbols within each signalframe identified based on a frame index.

Furthermore, the frequency interleaver may generate various interleavingseeds by cyclically shifting a main interleaving seed by the symboloffset with respect to each OFDM symbol.

As illustrated in a block 51200 placed on the upper side of FIG. 51, thefrequency interleaver may perform random FI on cells included in eachOFDM symbol using an input cell index.

The parameters of random FI may be generated by a random FI generatorincluded in the frequency interleaver.

As illustrated in FIG. 51, S_(└j/2┘) denotes a random symbol offset usedin a j-th OFDM symbol, and a symbol └•┘ denotes floor operation.

C_(j)(k) denotes random FI used in the j-th OFDM symbol, N_(sym) denotesthe number of OFDM symbols within a single frame, and N_(data) denotesthe number of data cell(s) within a single OFDM symbol.

The relationship between S_(└j/2┘) and C_(j)(k) is described in detailbelow with reference to FIG. 52.

FIG. 52 illustrates the equation of the logical operation mechanism offrequency interleaving applied to a single super frame in accordancewith an embodiment of the present invention.

That is, FIG. 52 illustrates the relationship between the aforementionedsymbol offset parameter and the parameter of random FI applied to a cellincluded in each OFDM.

As illustrated in FIG. 52, an offset to be used in each OFDM symbol maybe generated through the hierarchical structure of the aforementionedsymbol offset generator.

In this case, the symbol offset generator may be designed using aspecific random generator.

As described above, g_(sym) denotes a random symbol offset generatorused in a symbol interleaver, and g_(data) denotes a random (FI)generator used in a cell interleaver.

FIG. 53 is a diagram illustrating the single-memory deinterleaving ofinput-sequential OFDM symbols which is proposed in this specification.

FIG. 53 is a diagram illustrating that the operation of the frequencydeinterleaver of the broadcasting signal reception apparatus orbroadcasting signal reception apparatus for performing deinterleavinghas been conceptualized by applying interleaving seeds used in thebroadcasting signal transmission apparatus (or frequency interleaver) toa pair-wise OFDM symbol.

The frequency deinterleaver includes in the frame parsing block, asillustrated in FIG. 31.

The frame parsing block may also be represented by a deframing &deinterleaver block.

As described above, the broadcasting signal reception apparatus inaccordance with an embodiment of the present invention may perform aprocess opposite the aforementioned frequency interleaving process usinga single piece of memory.

FIG. 54 is a flowchart illustrating an example of a method oftransmitting a broadcasting signal which is proposed in thisspecification.

Referring to FIG. 54, the broadcast signal transmission apparatusproposed in this specification processes input streams or input datapackets through an input formatting module at step S5410.

The input data packets may include a variety of types of packets.

That is, the input formatting module of the broadcast signaltransmission apparatus formats the input data packets into multiple (ora plurality of or at least one or one or more) Data Pipes (DPs) ormultiple Physical Layer Pipes (PLPs).

In this case, the plurality of DPs or the plurality of PLPs may berepresented by a plurality of data transmission channels.

Thereafter, the broadcast signal transmission apparatus encodes the dataof the plurality of formatted PLPs for each PLP through a BitInterleaved Coding and Modulation (BICM) module at step S5420.

The BICM module may also be represented by the encoder.

Accordingly, the broadcast signal transmission apparatus encodes datacorresponding to each of data transmission channels through whichservice data or service component data is transmitted through theencoder.

Thereafter, the broadcast signal transmission apparatus generates atleast one signal frame by mapping the encoded data of the PLPs through aframe building module at step S5430.

The frame building module may be represented by the frame builder or theframing & interleaving block.

The signal frame denotes the aforementioned ATSC 3.0 frame.

As described above, the ATSC 3.0 frame includes a preamble. The preambleincludes the frequency interleaver mode (FI_MODE) information proposedin this specification.

Furthermore, the preamble is placed after a bootstrap and before a datapayload.

For the structure of the ATSC 3.0 frame and a related description,reference is made to FIG. 40.

The FI_MODE information may be included in L1 signaling included in thepreamble.

The L1-signaling may be divided into the two parts, that is, L1-staticand L1-dynamic, as described with reference to FIG. 40.

In this case, the FI_MODE information may be included in the L1-staticand/or the L1-dynamic.

The frequency interleaver (FI) mode (FI_MODE) information included inthe preamble denotes information indicating whether FI is available.Whether FI is available may be indicated by on or off.

That is, the FI mode information indicates whether FI is on or off, andmay be represented by 1 bit.

If the FI mode has been set as on (or if the FI mode denotes on), datacell output by the cell mapper is subjected to frequency interleavingfor each OFDM symbol through FI.

The FI mode information may be represented by FI mode signaling.

For example, if the FI mode information has been set to “1”, it maydenote that FI has been on. On the contrary, if the FI mode informationhas been set to “0”, it may denote that the FI has been off.

More specifically, the FI mode information may be transmitted through L1Signaling within a frame.

In this case, a preamble symbol(s) transmits L1 signaling data for datasymbol(s) subsequent to the preamble symbol(s).

The preamble symbol(s) are placed after a bootstrap and placed before adata symbol(s).

The L1 signaling provides required information for configuring physicallayer parameters. L1 means Layer-1 corresponding to the lowest layer ofthe ISO 7 layer model.

Furthermore, the L1 signaling is included in the preamble, and includestwo parts, that is, L1-static and L1-dynamic.

A method of transmitting a transmission broadcast signal through the FImode information proposed in this specification is described in moredetail.

The broadcast signal transmission apparatus includes the FI modeinformation, newly defined in this specification, in a preamble(Specifically, L1-signaling, L1-static, or L1-dynamic).

Thereafter, the broadcast signal transmission apparatus performs or doesnot perform an FI operation depending on an FI mode information settingvalue included in the preamble.

Thereafter, the broadcast signal transmission apparatus modulates thedata of the generated signal frame using an OFDM method through anOrthogonal Frequency Division Multiplexing Generation (OFDM) module andtransmits a broadcasting signal, including the modulated data of thesignal frame, through the broadcasting signal transmission apparatus(i.e., a broadcasting transmitter) at step S5440.

FIG. 55 is a flowchart illustrating an example of a method of receivinga broadcast signal which is proposed in this specification.

Referring to FIG. 55, the broadcast signal reception apparatus proposedin this specification receives an external broadcast signal through asynchronization and demodulation module and demodulates the data of thereceived broadcasting signal using an OFDM method at step S5510.

The synchronization and demodulation module may also be represented by areceiver and a demodulator.

Accordingly, the broadcast signal reception apparatus receives thebroadcast signal, including at least one signal frame, through thereceiver and demodulates the data of the received broadcasting signalthrough the demodulator using an Orthogonal Frequency DivisionMultiplexing (OFDM) method.

Thereafter, the broadcast signal reception apparatus parses thedemodulated data into at least one signal frame through a frame parsingmodule at step S5520.

The frame parsing module may also be represented by a frame parser ordeframing and deinterleaving.

Accordingly, the broadcast signal reception apparatus parses the atleast one signal frame included in the received broadcast signal inorder to extract service data or service component data through theframe parser.

The signal frame denotes the aforementioned ATSC 3.0 frame.

As described above, the ATSC 3.0 frame includes a preamble. The preambleincludes the frequency interleaver mode (FI_MODE) information proposedin this specification.

Furthermore, the preamble is placed after a bootstrap and placed beforea data payload.

For the structure of the ATSC 3.0 frame and a related descriptionthereof, reference is made to FIG. 40.

The FI_MODE information may be included in L1 signaling included in thepreamble.

The L1-signaling may be divided into two parts, that is, L1-static andL1-dynamic, as described with reference to FIG. 40.

In this case, the FI_MODE information may be included in the L1-staticand/or the L1-dynamic.

The frequency interleaver (FI) mode (FI_MODE) information included inthe preamble is information indicating whether FI is available. WhetherFI is available may be indicated by on or off.

That is, the FI mode information denotes whether FI has been on or off,and may be represented by 1 bit.

If the FI mode has been set as on (or if the FI mode is on), frequencyinterleaving is performed on data cells, output by the cell mapper, foreach OFDM symbol through FI.

The FI mode information may be represented by FI mode signaling.

For example, if the FI mode information has been set to “1”, it maydenote that FI has been on. On the contrary, if the FI mode informationhas been set to “0”, it may denote that the FI has been off.

More specifically, the FI mode information may be transmitted through L1signaling within a frame.

In this case, a preamble symbol(s) transmits L1 signaling data for adata symbol(s) subsequent to the preamble symbol(s).

The preamble symbol(s) is placed after a bootstrap and placed before thedata symbol(s).

The L1 signaling provides required information for configuring physicallayer parameters. L1 means Layer-1 corresponding to the lowest layer ofthe ISO 7 layer model.

Furthermore, the L1 signaling is included in the preamble, and includestwo parts, that is, L1-static and L1-dynamic.

In this case, a method of parsing, by the broadcast signal receptionapparatus, the signal frame including the FI mode information isdescribed in more detail.

That is, the broadcast signal reception apparatus checks whether an FIoperation has been performed by the broadcast signal transmissionapparatus based on received (or detected or decoded) FI modeinformation.

If, as a result of the check, the FI operation is found to have beenperformed (if the FI mode information value has been set as “on”), thebroadcast signal reception apparatus additionally performs frequencydeinterleaving (FDI).

That is, the broadcast signal reception apparatus performs or does notperform the FDI operation based on the FI mode information setting valueincluded in the preamble.

Thereafter, the broadcast signal reception apparatus decodes the parsedat least one signal frame into a plurality of DPs or a plurality of PLPsthrough a demapping and decoding module at step S5530.

The demapping and decoding module may also be represented by a converterand a decoder.

Accordingly, the broadcast signal reception apparatus converts servicedata or service component data into bits through the converter anddecodes the converted bits through the decoder.

Thereafter, the broadcast signal reception apparatus restores aplurality of DPs or a plurality of PLPs, output by the demapping anddecoding module, to the input streams or the input data packets throughan output processor module at step S5540.

In some embodiments, the broadcast signal reception apparatus may outputthe data streams or data packets including the decoded bits through anoutput processor.

An embodiment of the present invention can provide various broadcastingservices by processing data according to service characteristics andcontrolling Quality of Service (QoS) for each service or servicecomponent.

Furthermore, an embodiment of the present invention can achievetransmission flexibility by transmitting various broadcasting servicesthrough the same Radio Frequency (RF) signal bandwidth.

Furthermore, an embodiment of the present invention can improve datatransfer efficiency and the transmission/reception robustness of abroadcasting signal using a Multiple-Input Multiple-Output (MIMO)system.

Furthermore, an embodiment of the present invention can provide thebroadcast signal transmission/reception methods and apparatuses, whereina digital broadcast signal can be received without an error although amobile reception apparatus is used or an indoor environment.

Furthermore, this specification is advantageous in that a frequencydiversity effect can be maximized using a different interleaving seedfor each OFDM symbol pair in the frequency interleaver (FI).

Furthermore, this specification is advantageous in that it can improvedata restoration speed by transmitting information indicating whether afrequency interleaver has been used through a preamble in advance sothat the broadcast signal reception apparatus is previously aware ofwhether frequency interleaving has been performed on a received signalprior to data decoding.

Furthermore, this specification is advantageous in that it can supportFDM by turning off an FI operation through the operation of FI modeinformation for turning on or off the FI operation.

Advantages to be obtained in this specification are not limited to theaforementioned advantages and may include various other advantages thatare evident to those skilled in the art to which the present inventionpertains from the following description.

This specification relates to a method and apparatus for receiving andtransmitting broadcasting signals.

Those skilled in the art will understand that the present invention maybe modified in various ways without departing from the spirit or rangeof the present invention. Accordingly, the present invention has beenintended to include all changes and modifications of the presentinvention provided within the attached claims and equivalent rangesthereof.

In this specification, both apparatus and method inventions have beendescribed, and descriptions of both the apparatus and method inventionsmay be mutually supplemented and applied.

What is claimed: 1.-7. (canceled)
 8. A reception apparatus for receivinga broadcast signal, comprising: a receiver configured to receive thebroadcast signal including a signal frame, wherein the signal frameincludes preamble, wherein the preamble includes control informationindicating whether a frequency interleaving is enabled or not; ademodulator configured to demodulate the received broadcast signal byOrthogonal Frequency Division Multiplexing (OFDM) scheme; a frequencydeinterleaver configured to selectively perform frequency deinterleavingon data in the signal frame based on the control information; ade-mapper configured to de-map Physical Layer Pipe (PLP) data in thesignal frame; a bit deinterleaver configured to bit-deinterleave the PLPdata; a Forward Error Correction (FEC) decoder configured to FEC-decodethe PLP data; and an output processor configured to output a datastream, wherein when the control information has a first value, thefrequency deinterleaver is enabled and when the control information hasa second value, the frequency deinterleaver is disabled.
 9. Thereception apparatus of claim 8, wherein the frequency deinterleaving isperformed by using a different deinterleaving sequence for every symbolpair in the signal frame.
 10. The reception apparatus of claim 9,wherein the deinterleaving sequence is generated based on amain-sequence generated by a first generator and a symbol offsetgenerated by a second generator.
 11. The reception apparatus of claim10, wherein the main-sequence generated by the first generator isvariable based on an FFT size.
 12. The reception apparatus of claim 10,wherein the second generator generates a new offset for the every symbolpair and the symbol pair comprises two consecutive symbols.
 13. A methodof receiving a broadcast signal, comprising: receiving the broadcastsignal including a signal frame, wherein the signal frame includespreamble, wherein the preamble includes control information indicatingwhether a frequency interleaving is enabled or not; demodulating thereceived broadcast signal by Orthogonal Frequency Division Multiplexing(OFDM) scheme; selectively performing frequency deinterleaving on datain the signal frame based on the control information; de-mappingPhysical Layer Pipe (PLP) data in the signal frame; bit-deinterleavingthe PLP data; Forward Error Correction (FEC)-decoding the PLP data; andoutputting a data stream, wherein when the control information has afirst value, a frequency deinterleaver is enabled and when the controlinformation has a second value, the frequency deinterleaver is disabled.14. The method of claim 13, wherein the frequency deinterleaving isperformed by using a different deinterleaving sequence for every symbolpair in the signal frame.
 15. The method of claim 14, wherein thedeinterleaving sequence is generated based on a main-sequence generatedby a first generator and a symbol offset generated by a secondgenerator.
 16. The method of claim 15, wherein the main-sequencegenerated by the first generator is variable based on an FFT size. 17.The method of claim 16, wherein the second generator generates a newoffset for the every symbol pair and the symbol pair comprises twoconsecutive symbols.